j2c - npm Package Compare versions

Comparing version 1.0.0-3 to 1.0.0-4

.eslintrc.js

 module.exports = {
     rules: {
         indent: [
-            2, 2
+            "error", 2
         ],
         quotes: [
-            2,
+            "error",
             "single",
@@ -12,10 +12,12 @@ "avoid-escape"
         "linebreak-style": [
-            2,
+            "error",
             "unix"
         ],
         semi: [
-            2,
+            "error",
             "never"
         ],
-        "no-trailing-spaces": [2]
+        "no-trailing-spaces": "error",
+        "comma-dangle": "error",
+        "no-native-reassign": "error"
     },
@@ -22,0 +24,0 @@ parserOptions: {

dist/j2c.amd.js

 define(function () { 'use strict';
 
-  var emptyArray = [];
-  var emptyObject = {};
-  var type = emptyObject.toString;
-  var ARRAY =  type.call(emptyArray);
-  var OBJECT = type.call(emptyObject);
-  var STRING = type.call('');
-  var FUNCTION = type.call(type);
-  var own =  emptyObject.hasOwnProperty;
-  var freeze = Object.freeze || function(o) {return o};
-  function Default(target, source) {
-    for (var k in source) if (own.call(source, k)) {
-      if (k.indexOf('$') && !(k in target)) target[k] = source[k]
-    }
-    return target
-  }
+var emptyArray = [];
+var emptyObject = {};
+var type = emptyObject.toString;
+var ARRAY =  type.call(emptyArray);
+var OBJECT = type.call(emptyObject);
+var STRING = type.call('');
+var FUNCTION = type.call(type);
+var own =  emptyObject.hasOwnProperty;
+var freeze = Object.freeze || function(o) {return o};
 
-  function cartesian(a,b) {
-    var res = [], i, j
-    for (j in b) if(own.call(b, j))
-      for (i in a) if(own.call(a, i))
-        res.push(a[i] + b[j])
-    return res
+
+function defaults(target, source) {
+  for (var k in source) if (own.call(source, k)) {
+    if (k.indexOf('$') && !(k in target)) target[k] = source[k];
   }
+  return target
+}
 
-  // "Tokenizes" the selectors into parts relevant for the next function.
-  // Strings and comments are matched, but ignored afterwards.
-  // This is not a full tokenizers. It only recognizes comas, parentheses,
-  // strings and comments.
-  // regexp generated by scripts/regexps.js then trimmed by hand
-  var selectorTokenizer = /[(),]|"(?:\\.|[^"\n])*"|'(?:\\.|[^'\n])*'|\/\*[\s\S]*?\*\//g
+function cartesian(a,b) {
+  var res = [], i, j;
+  for (j in b) if(own.call(b, j))
+    for (i in a) if(own.call(a, i))
+      res.push(a[i] + b[j]);
+  return res
+}
 
+// "Tokenizes" the selectors into parts relevant for the next function.
+// Strings and comments are matched, but ignored afterwards.
+// This is not a full tokenizers. It only recognizes comas, parentheses,
+// strings and comments.
+// regexp generated by scripts/regexps.js then trimmed by hand
+var selectorTokenizer = /[(),]|"(?:\\.|[^"\n])*"|'(?:\\.|[^'\n])*'|\/\*[\s\S]*?\*\//g;
 
-  /**
-   * This will split a coma-separated selector list into individual selectors,
-   * ignoring comas in strings, comments and in :pseudo-selectors(parameter, lists).
-   * @param {string} selector
-   * @return {string[]}
-   */
 
-  function splitSelector(selector) {
-    var indices = [], res = [], inParen = 0, o
-    /*eslint-disable no-cond-assign*/
-    while (o = selectorTokenizer.exec(selector)) {
-    /*eslint-enable no-cond-assign*/
-      switch (o[0]) {
-      case '(': inParen++; break
-      case ')': inParen--; break
-      case ',': if (inParen) break; indices.push(o.index)
-      }
+/**
+ * This will split a coma-separated selector list into individual selectors,
+ * ignoring comas in strings, comments and in :pseudo-selectors(parameter, lists).
+ *
+ * @param {string} selector
+ * @return {string[]}
+ */
+
+function splitSelector(selector) {
+  var indices = [], res = [], inParen = 0, o;
+  /*eslint-disable no-cond-assign*/
+  while (o = selectorTokenizer.exec(selector)) {
+  /*eslint-enable no-cond-assign*/
+    switch (o[0]) {
+    case '(': inParen++; break
+    case ')': inParen--; break
+    case ',': if (inParen) break; indices.push(o.index);
     }
-    for (o = indices.length; o--;){
-      res.unshift(selector.slice(indices[o] + 1))
-      selector = selector.slice(0, indices[o])
-    }
-    res.unshift(selector)
-    return res
   }
+  for (o = indices.length; o--;){
+    res.unshift(selector.slice(indices[o] + 1));
+    selector = selector.slice(0, indices[o]);
+  }
+  res.unshift(selector);
+  return res
+}
 
-  // This is like the `selectorTokenizer`, but for the `&` operator
+// Like the `selectorTokenizer`, but for the `&` operator
+var ampersandTokenizer = /&|"(?:\\.|[^"\n])*"|'(?:\\.|[^'\n])*'|\/\*[\s\S]*?\*\//g;
 
-  var ampersandTokenizer = /&|"(?:\\.|[^"\n])*"|'(?:\\.|[^'\n])*'|\/\*[\s\S]*?\*\//g
-
-  function ampersand (selector, parents) {
-    var indices = [], split = [], res, o
-    /*eslint-disable no-cond-assign*/
-    while (o = ampersandTokenizer.exec(selector)) {
-    /*eslint-enable no-cond-assign*/
-      if (o[0] == '&') indices.push(o.index)
-    }
-    for (o = indices.length; o--;){
-      split.unshift(selector.slice(indices[o] + 1))
-      selector = selector.slice(0, indices[o])
-    }
-    split.unshift(selector)
-    res = [split[0]]
-    for (o = 1; o < split.length; o++) {
-      res = cartesian(res, cartesian(parents, [split[o]]))
-    }
-    return res.join(',')
+function ampersand (selector, parents) {
+  var indices = [], split = [], res, o;
+  /*eslint-disable no-cond-assign*/
+  while (o = ampersandTokenizer.exec(selector)) {
+  /*eslint-enable no-cond-assign*/
+    if (o[0] == '&') indices.push(o.index);
   }
-
-  function flatIter (f) {
-    return function iter(arg) {
-      if (type.call(arg) === ARRAY) for (var i= 0 ; i < arg.length; i ++) iter(arg[i])
-      else f(arg)
-    }
+  for (o = indices.length; o--;){
+    split.unshift(selector.slice(indices[o] + 1));
+    selector = selector.slice(0, indices[o]);
   }
+  split.unshift(selector);
+  if (split.length === 1) split.unshift('');
+  res = [split[0]];
+  for (o = 1; o < split.length; o++) {
+    res = cartesian(res, cartesian(parents, [split[o]]));
+  }
+  return res.join(',')
+}
 
-  function decamelize(match) {
-    return '-' + match.toLowerCase()
+function flatIter (f) {
+  return function iter(arg) {
+    if (type.call(arg) === ARRAY) for (var i= 0 ; i < arg.length; i ++) iter(arg[i]);
+    else f(arg);
   }
+}
 
-  /**
-   * Handles the property:value; pairs.
-   *
-   * @param {object} state - holds the localizer- and walker-related methods
-   *                         and state
-   * @param {object} emit - the contextual emitters to the final buffer
-   * @param {string} prefix - the current property or a prefix in case of nested
-   *                          sub-properties.
-   * @param {array|object|string} o - the declarations.
-   * @param {boolean} local - are we in @local or in @global scope.
-   */
+function decamelize(match) {
+  return '-' + match.toLowerCase()
+}
 
-  function declarations(state, emit, prefix, o, local) {
-    var k, v, kk
-    if (o==null) return
+/**
+ * Handles the property:value; pairs.
+ *
+ * @param {object} state - holds the localizer- and walker-related methods
+ *                         and state
+ * @param {object} emit - the contextual emitters to the final buffer
+ * @param {string} prefix - the current property or a prefix in case of nested
+ *                          sub-properties.
+ * @param {array|object|string} o - the declarations.
+ * @param {boolean} local - are we in @local or in @global scope.
+ */
 
-    switch ( type.call(o = o.valueOf()) ) {
-    case ARRAY:
-      for (k = 0; k < o.length; k++)
+function declarations(state, emit, prefix, o, local) {
+  var k, v, kk;
+  if (o==null) return
 
-        declarations(state, emit, prefix, o[k], local)
+  switch ( type.call(o = o.valueOf()) ) {
+  case ARRAY:
+    for (k = 0; k < o.length; k++)
 
-      break
-    case OBJECT:
-      // prefix is falsy iif it is the empty string, which means we're at the root
-      // of the declarations list.
-      prefix = (prefix && prefix + '-')
-      for (k in o) if (own.call(o, k)){
-        v = o[k]
-        if (/\$/.test(k)) {
-          for (kk in (k = k.split('$'))) if (own.call(k, kk)) {
+      declarations(state, emit, prefix, o[k], local);
 
-            declarations(state, emit, prefix + k[kk], v, local)
+    break
+  case OBJECT:
+    // prefix is falsy iif it is the empty string, which means we're at the root
+    // of the declarations list.
+    prefix = (prefix && prefix + '-');
+    for (k in o) if (own.call(o, k)){
+      v = o[k];
+      if (/\$/.test(k)) {
+        for (kk in (k = k.split('$'))) if (own.call(k, kk)) {
 
-          }
-        } else {
+          declarations(state, emit, prefix + k[kk], v, local);
 
-          declarations(state, emit, prefix + k, v, local)
-
         }
-      }
-      break
-    default:
-      // prefix is falsy when it is "", which means that we're
-      // at the top level.
-      // `o` is then treated as a `property:value` pair, or a
-      // semi-colon-separated list thereof.
-      // Otherwise, `prefix` is the property name, and
-      // `o` is the value.
+      } else {
 
-      // restore the dashes
-      k = prefix.replace(/_/g, '-').replace(/[A-Z]/g, decamelize)
+        declarations(state, emit, prefix + k, v, local);
 
-      if (local && (k == 'animation-name' || k == 'animation' || k == 'list-style')) {
-        // no need to tokenize here a plain `.split(',')` has all bases covered.
-        // We may 'localize' a comment, but it's not a big deal.
-        o = o.split(',').map(function (o) {
+      }
+    }
+    break
+  default:
+    // prefix is falsy when it is "", which means that we're
+    // at the top level.
+    // `o` is then treated as a `property:value` pair, or a
+    // semi-colon-separated list thereof.
+    // Otherwise, `prefix` is the property name, and
+    // `o` is the value.
 
-          return o.replace(/(var\([^)]+\))|:?global\(\s*([_A-Za-z][-\w]*)\s*\)|()(-?[_A-Za-z][-\w]*)/, state.L)
+    // restore the dashes
+    k = prefix.replace(/_/g, '-').replace(/[A-Z]/g, decamelize);
 
-        }).join(',')
-      }
+    if (local && (k == 'animation-name' || k == 'animation' || k == 'list-style')) {
+      // no need to tokenize here a plain `.split(',')` has all bases covered.
+      // We may 'localize' a comment, but it's not a big deal.
+      o = o.split(',').map(function (o) {
 
-      emit.d(k, o)
+        return o.replace(/^\s*(?:(var\([^)]+\))|:?global\(\s*([_A-Za-z][-\w]*)\s*\)|()(-?[_A-Za-z][-\w]*))/, state.localizeReplacer)
 
+      }).join(',');
     }
-  }
 
-  /**
-   * Hanldes at-rules
-   *
-   * @param {object} state - holds the localizer- and walker-related methods
-   *                         and state
-   * @param {object} emit - the contextual emitters to the final buffer
-   * @param {array} k - The parsed at-rule, including the parameters,
-   *                    if takes both parameters and a block.
-   * @param {string} prefix - the current selector or the selector prefix
-   *                          in case of nested rules
-   * @param {string|string[]|object|object[]} v - Either parameters for
-   *                                              block-less rules or
-   *                                              their block
-   *                                              for the others.
-   * @param {string} inAtRule - are we nested in an at-rule?
-   * @param {boolean} local - are we in @local or in @global scope?
-   */
+    emit.decl(k, o);
 
-  function atRules(state, emit, k, v, prefix, local, inAtRule) {
+  }
+}
 
-    for (var i = 0; i < state.$a.length; i++) {
+/**
+ * Handles a single at-rules
+ *
+ * @param {object} state - holds the localizer- and walker-related methods
+ *                         and state
+ * @param {object} emit - the contextual emitters to the final buffer
+ * @param {array} k - The parsed at-rule, including the parameters,
+ *                    if takes both parameters and a block.
+ *                    k == [match, fullAtRule, atRuleType, params?]
+ *                    So in `@-webkit-keyframes foo`, we have
+ *                     - match = "@-webkit-keyframes foo"
+ *                     - fullAtRule = "@-webkit-keyframes"
+ *                     - atRuleType = "keyframes"
+ *                     - params = "foo"
+ * @param {string|string[]|object|object[]} v - Either parameters for
+ *                                              block-less rules or
+ *                                              their block
+ *                                              for the others.
+ * @param {string} prefix - the current selector or the selector prefix
+ *                          in case of nested rules
+ * @param {boolean} local - are we in @local or in @global scope?
+ * @param {string} nestingDepth - are we nested in an at-rule or a selector?
+ */
 
-      if (state.$a[i](state, emit, k, v, prefix, local, inAtRule)) return
+function atRules(state, emit, k, v, prefix, local, nestingDepth) {
 
-    }
+  // First iterate over user-provided at-rules and return if one of them corresponds to the current one
+  for (var i = 0; i < state.$atHandlers.length; i++) {
 
-    // using `/^global$/.test(k[2])` rather that 'global' == k[2] gzips
-    // slightly better because of the regexps test further down.
-    // It is slightly less efficient but this isn't a critical path.
+    if (state.$atHandlers[i](state, emit, k, v, prefix, local, nestingDepth)) return
 
-    if (!k[3] && /^global$/.test(k[2])) {
+  }
 
-      rules(state, emit, prefix, v, 0, inAtRule)
+  // using `/^global$/.test(k[2])` rather that 'global' == k[2] gzips
+  // slightly better thanks to the regexps tests further down.
+  // It is slightly less efficient but this isn't a critical path.
 
+  if (!k[3] && /^global$/.test(k[2])) {
 
-    } else if (!k[3] && /^local$/.test(k[2])) {
+    rules(state, emit, prefix, v, 0, nestingDepth);
 
-      rules(state, emit, prefix, v, 1, inAtRule)
 
+  } else if (!k[3] && /^local$/.test(k[2])) {
 
-    } else if (k[3] && /^adopt$/.test(k[2])) {
+    rules(state, emit, prefix, v, 1, nestingDepth);
 
-      if (!local || inAtRule) return emit.a('@-error-bad-at-adopt-placement' , JSON.stringify(k[0]), 0)
 
-      if (!/^\.?[_A-Za-z][-\w]*$/.test(k[3])) return emit.a('@-error-bad-at-adopter', k[3], 0)
+  } else if (k[3] && /^adopt$/.test(k[2])) {
 
-      i = []
-      flatIter(function(adoptee, asString) {
+    if (!local || nestingDepth) return emit.err('@adopt global or nested: ' + k[0])
 
-        if(!/^\.?[_A-Za-z][-\w]*(?:\s+\.?[_A-Za-z][-\w]*)*$/.test(asString = adoptee.toString())) emit.a('@-error-bad-at-adoptee', JSON.stringify(adoptee), 0)
+    if (!/^\.?[_A-Za-z][-\w]*$/.test(k[3])) return emit.err('bad adopter ' + JSON.stringify(k[3]) + ' in ' + k[0])
 
-        else i.push(asString.replace(/\./g, ''))
+    i = [];
+    flatIter(function(adoptee, asString) {
 
-      })(v)
+      if(adoptee == null || !/^\.?[_A-Za-z][-\w]*(?:\s+\.?[_A-Za-z][-\w]*)*$/.test(asString = adoptee + '')) emit.err('bad adoptee '+ JSON.stringify(adoptee) + ' in ' + k[0]);
 
-      // we may end up with duplicate classes but AFAIK it has no consequences on specificity.
-      if (i.length) {
-        state.l(k[3] = k[3].replace(/\./g, ''))
-        state.n[k[3]] += (' ' + i.join(' '))
-      }
+      else i.push(asString.replace(/\./g, ''));
 
+    })(v);
 
-    } else if (!k[3] && /^(?:namespace|import|charset)$/.test(k[2])) {
-      flatIter(function(v) {
+    // we may end up with duplicate classes but AFAIK it has no consequences on specificity.
+    if (i.length) {
+      state.localize(k[3] = k[3].replace(/\./g, ''));
+      state.names[k[3]] += (' ' + i.join(' '));
+    }
 
-        emit.a(k[0], v)
 
-      })(v)
+  } else if (!k[3] && /^(?:namespace|import|charset)$/.test(k[2])) {
+    flatIter(function(v) {
 
+      emit.atrule(k[1], k[2], v);
 
-    } else if (!k[3] && /^(?:font-face|viewport)$/.test(k[2])) {
-      flatIter(function(v) {
+    })(v);
 
-        emit.a(k[1], '', 1)
 
-        declarations(state, emit, '', v, local)
+  } else if (!k[3] && /^(?:font-face|viewport)$/.test(k[2])) {
+    flatIter(function(v) {
 
-        emit.A(k[1], '')
+      emit.atrule(k[1], k[2], k[3], 1);
 
-      })(v)
+      declarations(state, emit, '', v, local);
 
-    } else if (k[3] && /^(?:media|supports|page|keyframes)$/.test(k[2])) {
+      emit._atrule();
 
-      if (local && 'keyframes' == k[2]) {
-        k[3] = k[3].replace(
-          // generated by script/regexps.js
-          /(var\([^)]+\))|:?global\(\s*([_A-Za-z][-\w]*)\s*\)|()(-?[_A-Za-z][-\w]*)/,
-          state.L
-        )
-      }
+    })(v);
 
+  } else if (k[3] && /^(?:media|supports|page|keyframes)$/.test(k[2])) {
 
-      emit.a(k[1], k[3], 1)
+    if (local && 'keyframes' == k[2]) {
+      k[3] = k[3].replace(
+        // generated by script/regexps.js
+        /(var\([^)]+\))|:?global\(\s*([_A-Za-z][-\w]*)\s*\)|()(-?[_A-Za-z][-\w]*)/,
+        state.localizeReplacer
+      );
+    }
 
-      if ('page' == k[2]) {
 
-        declarations(state, emit, '', v, local)
+    emit.atrule(k[1], k[2], k[3], 1);
 
-      } else {
+    if ('page' == k[2]) {
 
-        rules(
-          state, emit,
-          'keyframes' == k[2] ? '' : prefix,
-          v, local, 1
-        )
+      declarations(state, emit, '', v, local);
 
-      }
-
-      emit.A(k[1], k[3])
-
     } else {
 
-      emit.a('@-error-unsupported-at-rule', JSON.stringify(k[0]))
+      rules(
+        state, emit,
+        'keyframes' == k[2] ? '' : prefix,
+        v, local, nestingDepth + 1
+      );
 
     }
-  }
 
-  /**
-   * Add rulesets and other CSS tree to the sheet.
-   *
-   * @param {object} state - holds the localizer- and walker-related methods
-   *                         and state
-   * @param {object} emit - the contextual emitters to the final buffer
-   * @param {string} prefix - the current selector or a prefix in case of nested rules
-   * @param {array|string|object} tree - a source object or sub-object.
-   * @param {string} inAtRule - are we nested in an at-rule?
-   * @param {boolean} local - are we in @local or in @global scope?
-   */
-  function rules(state, emit, prefix, tree, local, inAtRule) {
-    var k, v, inDeclaration, kk
+    emit._atrule();
 
-    switch (type.call(tree)) {
+  } else {
 
-    case OBJECT:
-      for (k in tree) if (own.call(tree, k)) {
-        v = tree[k]
+    emit.err('Unsupported at-rule: ' + k[0]);
 
-        if (prefix.length > 0 && /^[-\w$]+$/.test(k)) {
-          if (!inDeclaration) {
-            inDeclaration = 1
+  }
+}
 
-            emit.s(prefix)
+/**
+ * Add rulesets and other CSS tree to the sheet.
+ *
+ * @param {object} state - holds the localizer- and walker-related methods
+ *                         and state
+ * @param {object} emit - the contextual emitters to the final buffer
+ * @param {string} prefix - the current selector or a prefix in case of nested rules
+ * @param {array|string|object} tree - a source object or sub-object.
+ * @param {string} nestingDepth - are we nested in an at-rule?
+ * @param {boolean} local - are we in @local or in @global scope?
+ */
+function rules(state, emit, prefix, tree, local, nestingDepth) {
+  var k, v, inDeclaration, kk;
 
-          }
-          if (/\$/.test(k)) {
-            for (kk in (k = k.split('$'))) if (own.call(k, kk)) {
+  switch (type.call(tree)) {
 
-              declarations(state, emit, k[kk], v, local)
+  case OBJECT:
+    for (k in tree) if (own.call(tree, k)) {
+      v = tree[k];
 
-            }
-          } else {
+      if (prefix.length > 0 && /^[-\w$]+$/.test(k)) {
+        if (!inDeclaration) {
+          inDeclaration = 1;
 
-            declarations(state, emit, k, v, local)
+          emit.rule(prefix);
 
-          }
+        }
+        if (/\$/.test(k)) {
+          for (kk in (k = k.split('$'))) if (own.call(k, kk)) {
 
-        } else if (/^@/.test(k)) {
-          // Handle At-rules
-          inDeclaration = 0
+            declarations(state, emit, k[kk], v, local);
 
-          atRules(state, emit,
-            /^(.(?:-[\w]+-)?([_A-Za-z][-\w]*))\b\s*(.*?)\s*$/.exec(k) || [k,'@','',''],
-            v, prefix, local, inAtRule
-          )
-
+          }
         } else {
-          // selector or nested sub-selectors
-          inDeclaration = 0
 
-          rules(
-            state, emit,
-            // `prefix` ... Hefty. Ugly. Sadly necessary.
-            //
-            (prefix.length > 0 && (/,/.test(prefix) || /,/.test(k))) ?
+          declarations(state, emit, k, v, local);
 
-              /*0*/ (kk = splitSelector(prefix), splitSelector(
-                local ?
+        }
 
-                  k.replace(
-                    /("(?:\\.|[^"\n])*"|'(?:\\.|[^'\n])*'|\/\*[\s\S]*?\*\/)|:global\(\s*(\.-?[_A-Za-z][-\w]*)\s*\)|(\.)(-?[_A-Za-z][-\w]*)/g,
-                    state.L
-                  ) :
+      } else if (/^@/.test(k)) {
+        // Handle At-rules
+        inDeclaration = 0;
 
-                  k
-              ).map(function (k) {
-                return /&/.test(k) ? ampersand(k, kk) : kk.map(function(kk) {
-                  return kk + k
-                }).join(',')
-              }).join(',')) :
+        atRules(state, emit,
+          /^(.(?:-[\w]+-)?([_A-Za-z][-\w]*))\b\s*(.*?)\s*$/.exec(k) || [k,'@','',''],
+          v, prefix, local, nestingDepth
+        );
 
-              /*0*/ /&/.test(k) ?
+      } else {
+        // selector or nested sub-selectors
+        inDeclaration = 0;
 
-                /*1*/ ampersand(
-                  local ?
+        rules(
+          state, emit,
+          // build the selector `prefix` for the next iteration.
+          // ugly and full of redundant bits but so far the fastest/shortest.gz
+          /*0 if*/(prefix.length > 0 && (/,/.test(prefix) || /,/.test(k))) ?
 
-                    k.replace(
-                      /("(?:\\.|[^"\n])*"|'(?:\\.|[^'\n])*'|\/\*[\s\S]*?\*\/)|:global\(\s*(\.-?[_A-Za-z][-\w]*)\s*\)|(\.)(-?[_A-Za-z][-\w]*)/g,
-                      state.L
-                    ) :
+            /*0 then*/ (kk = splitSelector(prefix), splitSelector(
+              local ?
 
-                    k,
-                  [prefix]
+                k.replace(
+                  /("(?:\\.|[^"\n])*"|'(?:\\.|[^'\n])*'|\/\*[\s\S]*?\*\/)|:global\(\s*(\.-?[_A-Za-z][-\w]*)\s*\)|(\.)(-?[_A-Za-z][-\w]*)/g,
+                  state.localizeReplacer
                 ) :
 
-                /*1*/ prefix + (
-                  local ?
+                k
+            ).map(function (k) {
+              return /&/.test(k) ? ampersand(k, kk) : kk.map(function(kk) {
+                return kk + k
+              }).join(',')
+            }).join(',')) :
 
-                    k.replace(
-                      /("(?:\\.|[^"\n])*"|'(?:\\.|[^'\n])*'|\/\*[\s\S]*?\*\/)|:global\(\s*(\.-?[_A-Za-z][-\w]*)\s*\)|(\.)(-?[_A-Za-z][-\w]*)/g,
-                      state.L
-                    ) :
+            /*0 else*/ /*1 if*/ /&/.test(k) ?
 
-                    k
-                  ),
-             v, local, inAtRule
-          )
+              /*1 then*/ ampersand(
+                local ?
 
-        }
-      }
+                  k.replace(
+                    /("(?:\\.|[^"\n])*"|'(?:\\.|[^'\n])*'|\/\*[\s\S]*?\*\/)|:global\(\s*(\.-?[_A-Za-z][-\w]*)\s*\)|(\.)(-?[_A-Za-z][-\w]*)/g,
+                    state.localizeReplacer
+                  ) :
 
-      break
+                  k,
+                [prefix]
+              ) :
 
-    case ARRAY:
-      for (k = 0; k < tree.length; k++){
+              /*1 else*/ prefix + (
+                local ?
 
-        rules(state, emit, prefix, tree[k], local, inAtRule)
+                  k.replace(
+                    /("(?:\\.|[^"\n])*"|'(?:\\.|[^'\n])*'|\/\*[\s\S]*?\*\/)|:global\(\s*(\.-?[_A-Za-z][-\w]*)\s*\)|(\.)(-?[_A-Za-z][-\w]*)/g,
+                    state.localizeReplacer
+                  ) :
 
+                  k
+                ),
+           v, local, nestingDepth + 1
+        );
+
       }
-      break
+    }
 
-    case STRING:
-      // CSS hacks or ouptut of `j2c.inline`.
+    break
 
-      emit.s(prefix.length > 0 ? prefix : ':-error-no-selector')
+  case ARRAY:
+    for (k = 0; k < tree.length; k++){
 
-      declarations(state, emit, '', tree, local)
+      rules(state, emit, prefix, tree[k], local, nestingDepth);
 
     }
-  }
+    break
 
-  // This is the first entry in the filters array, which is
-  // actually the last step of the compiler. It inserts
-  // closing braces to close normal (non at-) rules (those
-  // that start with a selector). Doing it earlier is
-  // impossible without passing state around in unrelated code
-  // or ending up with duplicated selectors when the source tree
-  // contains arrays.
-  // There's no `S` handler, because the core compiler never
-  // calls it.
-  function closeSelectors(next, inline) {
-    var lastSelector
-    return inline ? next : {
-      i: function(){lastSelector = 0; next.i()},
-      x: function (raw) {
-        if (lastSelector) {next.S(); lastSelector = 0}
-        return next.x(raw)
-      },
-      a: function (rule, param, takesBlock) {
-        if (lastSelector) {next.S(); lastSelector = 0}
-        next.a(rule, param, takesBlock)
-      },
-      A: function (rule) {
-        if (lastSelector) {next.S(); lastSelector = 0}
-        next.A(rule)
-      },
-      s: function (selector) {
-        if (selector !== lastSelector){
-          if (lastSelector) next.S()
-          next.s(selector)
-          lastSelector = selector
-        }
-      },
-      d: next.d
-    }
-  }
+  case STRING:
+    // CSS hacks or ouptut of `j2c.inline`.
+    if (!prefix.length) emit.err('No selector');
+    emit.rule(prefix || ' ');
 
-  function global(x) {
-    return ':global(' + x + ')'
-  }
+    declarations(state, emit, '', tree, local);
 
-  function kv (k, v, o) {
-    o = {}
-    o[k] = v
-    return o
   }
+}
 
-  function at (rule, params, block) {
-    if (
-      arguments.length < 3
-    ) {
-      // inner curry!
-      var _at = at.bind.apply(at, [null].concat([].slice.call(arguments,0)))
-      // So that it can be used as a key in an ES6 object literal.
-      _at.toString = function(){return '@' + rule + ' ' + params}
-      return _at
+// This is the first entry in the filters array, which is
+// actually the last step of the compiler. It inserts
+// closing braces to close normal (non at-) rules (those
+// that start with a selector). Doing it earlier is
+// impossible without passing state around in unrelated code
+// or ending up with duplicated selectors when the source tree
+// contains arrays.
+// There's no `_rule` handler, because the core compiler never
+// calls it.
+function closeSelectors(next, inline) {
+  var lastSelector;
+  return inline ? next : {
+    init: function(){lastSelector = 0; next.init();},
+    done: function (raw) {
+      if (lastSelector) {next._rule(); lastSelector = 0;}
+      return next.done(raw)
+    },
+    atrule: function (rule, kind, param, takesBlock) {
+      if (lastSelector) {next._rule(); lastSelector = 0;}
+      next.atrule(rule, kind, param, takesBlock);
+    },
+    _atrule: function (rule) {
+      if (lastSelector) {next._rule(); lastSelector = 0;}
+      next._atrule(rule);
+    },
+    rule: function (selector) {
+      if (selector !== lastSelector){
+        if (lastSelector) next._rule();
+        next.rule(selector);
+        lastSelector = selector;
+      }
     }
-    else return kv('@' + rule +' ' + params, block)
   }
+}
 
-  function j2c() {
+function global(x) {
+  return ':global(' + x + ')'
+}
 
-    // palceholder for the buffer used by the `$sink` handlers
-    var buf
+function kv (k, v, o) {
+  o = {};
+  o[k] = v;
+  return o
+}
 
-    // the bottom of the 'codegen' stream. Mirrors the `$filter` plugin API.
-    var $sink = {
-      // Init
-      i: function(){buf=[]},
-      // done (eXit)
-      x: function (raw) {return raw ? buf : buf.join('')},
-      // start At-rule
-      a: function (rule, argument, takesBlock) {
-        buf.push(rule, argument && ' ',argument, takesBlock ? ' {\n' : ';\n')
-      },
-      // end At-rule
-      A: function ()            {buf.push('}\n')},
-      // start Selector
-      s: function (selector)    {buf.push(selector, ' {\n')},
-      // end Selector
-      S: function ()            {buf.push('}\n')},
-      // declarations
-      d: function (prop, value) {buf.push(prop, prop && ':', value, ';\n')}
-    }
+function at (rule, params, block) {
+  if (
+    arguments.length < 3
+  ) {
+    // inner curry!
+    var _at = at.bind.apply(at, [null].concat([].slice.call(arguments,0)));
+    // So that it can be used as a key in an ES6 object literal.
+    _at.toString = function(){return '@' + rule + ' ' + params};
+    return _at
+  }
+  else return kv('@' + rule +' ' + params, block)
+}
 
-    var $filters = [closeSelectors]
-    var $atHandlers = []
+function j2c() {
 
-    var _instance = {
-      at: at,
-      global: global,
-      kv: kv,
-      names: {},
-      suffix: '__j2c-' +
-        Math.floor(Math.random() * 0x100000000).toString(36) + '-' +
-        Math.floor(Math.random() * 0x100000000).toString(36) + '-' +
-        Math.floor(Math.random() * 0x100000000).toString(36) + '-' +
-        Math.floor(Math.random() * 0x100000000).toString(36),
-      use: function() {
-        _use(emptyArray.slice.call(arguments))
-        return _instance
-      },
-      $plugins: []
-    }
+  // the buffer that accumulates the output. Initialized in `$sink.i()`
+  var buf, err;
 
-    var _streams = []
+  // the bottom of the 'codegen' stream. Mirrors the `$filter` plugin API.
+  var $sink = {
+    init: function(){buf=[], err=[];},
+    done: function (raw) {
+      if (err.length != 0) throw new Error('j2c error(s): ' + JSON.stringify(err,null,2) + 'in context:\n' + buf.join(''))
+      return raw ? buf : buf.join('')
+    },
+    err: function(msg) {
+      err.push(msg);
+      buf.push('/* +++ ERROR +++ ' + msg + ' */\n');
+    },
+    atrule: function (rule, kind, param, takesBlock) {
+      buf.push(rule, param && ' ', param, takesBlock ? ' {' : ';', _instance.endline);
+    },
+    // close atrule
+    _atrule: function () {buf.push('}', _instance.endline);},
+    rule: function (selector) {buf.push(selector, ' {', _instance.endline);},
+    // close rule
+    _rule: function () {buf.push('}', _instance.endline);},
+    decl: function (prop, value) {buf.push(prop, prop && ':', value, ';', _instance.endline);}
+  };
 
-    // The `state` (for the core) / `walker` (for the plugins) tables.
+  // holds the `$filter` and `$at` handlers
+  var $filters = [closeSelectors];
+  var $atHandlers = [];
 
-    var _walkers = [
-      // for j2c.sheet
-      {
-        // helpers for locaizing class and animation names
-        L: _localizeReplacer, // second argument to String.prototype.replace
-        l: _localize,         // mangles local names
-        n: _instance.names,    // local => mangled mapping
-        $a: $atHandlers,      // extra at-rules
-        // The core walker methods, to be provided to plugins
-        a: atRules,
-        d: declarations,
-        r: rules
-      },
-      // likewise, for j2c.inline (idem with `$a`, `a` and `s` removed)
-      {
-        L: _localizeReplacer,
-        l: _localize,
-        n: _instance.names,
-        d: declarations
-      }
-    ]
-
-
-    // The main API functions
-
-    _instance.sheet = function(tree) {
-      var emit = _getStream(0)
-      emit.i()
+  // the public API (see the main docs)
+  var _instance = {
+    at: at,
+    global: global,
+    kv: kv,
+    names: {},
+    endline: '\n',
+    suffix: '__j2c-' +
+      // 128 bits of randomness
+      Math.floor(Math.random() * 0x100000000).toString(36) + '-' +
+      Math.floor(Math.random() * 0x100000000).toString(36) + '-' +
+      Math.floor(Math.random() * 0x100000000).toString(36) + '-' +
+      Math.floor(Math.random() * 0x100000000).toString(36),
+    $plugins: [],
+    sheet: function(tree) {
+      var emit = _createOrRetrieveStream(0);
+      emit.init();
       rules(
         _walkers[0],
         emit,
-        '',    // prefix
+        '', // prefix
         tree,
-        1,      // local, by default
-        0     // inAtRule
-      )
+        1,  // local, by default
+        0   // nesting depth
+      );
 
-      return emit.x()
-    }
-
-    _instance.inline = function (tree) {
-      var emit = _getStream(1)
-      emit.i()
+      return emit.done()
+    },
+    inline: function (tree, options) {
+      var emit = _createOrRetrieveStream(1);
+      emit.init();
       declarations(
         _walkers[1],
         emit,
-        '',         // prefix
+        '', // prefix
         tree,
-        1           //local
-      )
-      return emit.x()
+        !(options && options.global)   // local, by default
+      );
+      return emit.done()
     }
+  };
 
-    // inner helpers
+  // The `state` (for the core functions) / `walker` (for the plugins) tables.
+  var _walkers = [
+    // for j2c.sheet
+    {
+      // helpers for locaizing class and animation names
+      localizeReplacer: _localizeReplacer, // second argument to String.prototype.replace
+      localize: _localize,                 // mangles local names
+      names: _instance.names,              // local => mangled mapping
+      $atHandlers: $atHandlers,            // extra at-rules
+      // The core walker methods, to be provided to plugins
+      atrule: atRules,
+      decl: declarations,
+      rule: rules
+    },
+    // likewise, for j2c.inline (idem with `$a`, `a` and `s` removed)
+    {
+      localizeReplacer: _localizeReplacer,
+      localize: _localize,
+      names: _instance.names,
+      decl: declarations
+    }
+  ];
 
-    var _use = flatIter(function(plugin) {
-      // `~n` is falsy for `n === -1` and truthy otherwise.
-      // Works well to turn the  result of `a.indexOf(x)`
-      // into a value that reflects the presence of `x` in
-      // `a`.
-      if (~_instance.$plugins.indexOf(plugin)) return
 
-      _instance.$plugins.push(plugin)
+  // inner helpers
 
-      if (type.call(plugin) === FUNCTION) plugin = plugin(_instance)
+  var _use = flatIter(function(plugin) {
+    // `~n` is falsy for `n === -1` and truthy otherwise.
+    // Works well to turn the  result of `a.indexOf(x)`
+    // into a value that reflects the presence of `x` in
+    // `a`.
+    if (~_instance.$plugins.indexOf(plugin)) return
 
-      if (!plugin) return
+    _instance.$plugins.push(plugin);
 
-      flatIter(function(filter) {
-        $filters.push(filter)
-      })(plugin.$filter || emptyArray)
+    if (type.call(plugin) === FUNCTION) plugin = plugin(_instance);
 
-      flatIter(function(handler) {
-        $atHandlers.push(handler)
-      })(plugin.$at || emptyArray)
+    if (!plugin) return
 
-      Default(_instance.names, plugin.$names || emptyObject)
+    flatIter(function(filter) {
+      $filters.push(filter);
+    })(plugin.$filter || emptyArray);
 
-      _use(plugin.$plugins || emptyArray)
+    flatIter(function(handler) {
+      $atHandlers.push(handler);
+    })(plugin.$at || emptyArray);
 
-      $sink = plugin.$sink || $sink
+    defaults(_instance.names, plugin.$names || emptyObject);
 
-      Default(_instance, plugin)
-    })
+    _use(plugin.$plugins || emptyArray);
 
-    function _getStream(inline) {
-      if (!_streams.length) {
-        for(var i = 0; i < 2; i++){
-          $filters[$filters.length - i] = function(_, inline) {return inline ? {i:$sink.i, d:$sink.d, x:$sink.x} : $sink}
-          for (var j = $filters.length; j--;) {
-            _streams[i] = freeze(Default(
-              $filters[j](_streams[i], !!i, _walkers[i]),
+    $sink = plugin.$sink || $sink;
+
+    defaults(_instance, plugin);
+  });
+
+
+  var _streams = [];
+  /**
+   * returns the codegen streams, creating them if necessary
+   * @param
+   */
+  function _createOrRetrieveStream(inline) {
+    // build the stream processors if needed
+    if (!_streams.length) {
+      // append the $sink as the ultimate filter
+      $filters.push(function(_, inline) {return inline ? {init:$sink.init, decl:$sink.decl, done:$sink.done, err: $sink.err} : $sink});
+      for(var i = 0; i < 2; i++){ // 0 for j2c.sheet, 1 for j2c.inline
+        for (var j = $filters.length; j--;) {
+          _streams[i] = freeze(
+            defaults(
+              $filters[j](_streams[i], !!i),
               _streams[i]
-            ))
-          }
+            )
+          );
         }
       }
-      var res = _streams[inline]
-      return res
     }
+    return _streams[inline]
+  }
 
-    function _localize(name) {
-      if (!_instance.names[name]) _instance.names[name] = name + _instance.suffix
-      return _instance.names[name].match(/^\S+/)
-    }
+  /**
+   * Returns a localized version of a given name.
+   * Registers the pair in `instnace.name` if needed.
+   *
+   * @param {string} name - the name to localize
+   * @return {string} - the localized version
+   */
+  function _localize(name) {
+    if (!_instance.names[name]) _instance.names[name] = name + _instance.suffix;
+    return _instance.names[name].match(/^\S+/)
+  }
 
-    function _localizeReplacer(match, string, global, dot, name) {
-      if (string || global) return string || global
-      return dot + _localize(name)
-    }
-
-    return _instance
+  /**
+   * Used as second argument for str.replace(localizeRegex, replacer)
+   * `ignore`, `global` and `(dot, name)` are mutually exclusive
+   *
+   * @param {string} match - the whole match (ignored)
+   * @param {string|null} ignore - a comment or a string literal
+   * @param {string|null} global - a global name
+   * @param {string|null} dot - either '.' for a local class name or the empty string otherwise
+   * @param {string|null} name - the name to localize
+   * @return {string}
+   */
+  function _localizeReplacer(match, ignore, global$$1, dot, name) {
+    return ignore || global$$1 || dot + _localize(name)
   }
 
-  var _j2c = j2c()
-  'sheet|inline|names|at|global|kv|suffix'.split('|').map(function(m){j2c[m] = _j2c[m]})
+  _use(emptyArray.slice.call(arguments));
+  return _instance
+}
 
-  return j2c;
+return j2c;
 
-});
+});

dist/j2c.amd.min.js

@@ -1,1 +0,1 @@
-define(function(){"use strict";function n(n,t){for(var e in t)S.call(t,e)&&(!e.indexOf("$")||e in n||(n[e]=t[e]));return n}function t(n,t){var e,r,a=[];for(r in t)if(S.call(t,r))for(e in n)S.call(n,e)&&a.push(n[e]+t[r]);return a}function e(n){for(var t,e=[],r=[],a=0;t=x.exec(n);)switch(t[0]){case"(":a++;break;case")":a--;break;case",":if(a)break;e.push(t.index)}for(t=e.length;t--;)r.unshift(n.slice(e[t]+1)),n=n.slice(0,e[t]);return r.unshift(n),r}function r(n,e){for(var r,a,i=[],s=[];a=_.exec(n);)"&"==a[0]&&i.push(a.index);for(a=i.length;a--;)s.unshift(n.slice(i[a]+1)),n=n.slice(0,i[a]);for(s.unshift(n),r=[s[0]],a=1;a<s.length;a++)r=t(r,t(e,[s[a]]));return r.join(",")}function a(n){return function t(e){if(d.call(e)===$)for(var r=0;r<e.length;r++)t(e[r]);else n(e)}}function i(n){return"-"+n.toLowerCase()}function s(n,t,e,r,a){var o,l,u;if(null!=r)switch(d.call(r=r.valueOf())){case $:for(o=0;o<r.length;o++)s(n,t,e,r[o],a);break;case v:e=e&&e+"-";for(o in r)if(S.call(r,o))if(l=r[o],/\$/.test(o))for(u in o=o.split("$"))S.call(o,u)&&s(n,t,e+o[u],l,a);else s(n,t,e+o,l,a);break;default:o=e.replace(/_/g,"-").replace(/[A-Z]/g,i),!a||"animation-name"!=o&&"animation"!=o&&"list-style"!=o||(r=r.split(",").map(function(t){return t.replace(/(var\([^)]+\))|:?global\(\s*([_A-Za-z][-\w]*)\s*\)|()(-?[_A-Za-z][-\w]*)/,n.L)}).join(",")),t.d(o,r)}}function o(n,t,e,r,i,o,u){for(var f=0;f<n.$a.length;f++)if(n.$a[f](n,t,e,r,i,o,u))return;if(!e[3]&&/^global$/.test(e[2]))l(n,t,i,r,0,u);else if(!e[3]&&/^local$/.test(e[2]))l(n,t,i,r,1,u);else if(e[3]&&/^adopt$/.test(e[2])){if(!o||u)return t.a("@-error-bad-at-adopt-placement",JSON.stringify(e[0]),0);if(!/^\.?[_A-Za-z][-\w]*$/.test(e[3]))return t.a("@-error-bad-at-adopter",e[3],0);f=[],a(function(n,e){/^\.?[_A-Za-z][-\w]*(?:\s+\.?[_A-Za-z][-\w]*)*$/.test(e=n.toString())?f.push(e.replace(/\./g,"")):t.a("@-error-bad-at-adoptee",JSON.stringify(n),0)})(r),f.length&&(n.l(e[3]=e[3].replace(/\./g,"")),n.n[e[3]]+=" "+f.join(" "))}else!e[3]&&/^(?:namespace|import|charset)$/.test(e[2])?a(function(n){t.a(e[0],n)})(r):!e[3]&&/^(?:font-face|viewport)$/.test(e[2])?a(function(r){t.a(e[1],"",1),s(n,t,"",r,o),t.A(e[1],"")})(r):e[3]&&/^(?:media|supports|page|keyframes)$/.test(e[2])?(o&&"keyframes"==e[2]&&(e[3]=e[3].replace(/(var\([^)]+\))|:?global\(\s*([_A-Za-z][-\w]*)\s*\)|()(-?[_A-Za-z][-\w]*)/,n.L)),t.a(e[1],e[3],1),"page"==e[2]?s(n,t,"",r,o):l(n,t,"keyframes"==e[2]?"":i,r,o,1),t.A(e[1],e[3])):t.a("@-error-unsupported-at-rule",JSON.stringify(e[0]))}function l(n,t,a,i,u,f){var c,g,p,h;switch(d.call(i)){case v:for(c in i)if(S.call(i,c))if(g=i[c],a.length>0&&/^[-\w$]+$/.test(c))if(p||(p=1,t.s(a)),/\$/.test(c))for(h in c=c.split("$"))S.call(c,h)&&s(n,t,c[h],g,u);else 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+define(function(){"use strict";function e(e,n){for(var t in n)b.call(n,t)&&(!t.indexOf("$")||t in e||(e[t]=n[t]));return e}function n(e,n){var t,r,l=[];for(r in n)if(b.call(n,r))for(t in e)b.call(e,t)&&l.push(e[t]+n[r]);return l}function t(e){for(var n,t=[],r=[],l=0;n=A.exec(e);)switch(n[0]){case"(":l++;break;case")":l--;break;case",":if(l)break;t.push(n.index)}for(n=t.length;n--;)r.unshift(e.slice(t[n]+1)),e=e.slice(0,t[n]);return r.unshift(e),r}function r(e,t){for(var r,l,a=[],i=[];l=S.exec(e);)"&"==l[0]&&a.push(l.index);for(l=a.length;l--;)i.unshift(e.slice(a[l]+1)),e=e.slice(0,a[l]);for(i.unshift(e),1===i.length&&i.unshift(""),r=[i[0]],l=1;l<i.length;l++)r=n(r,n(t,[i[l]]));return r.join(",")}function l(e){return function n(t){if(m.call(t)===$)for(var r=0;r<t.length;r++)n(t[r]);else e(t)}}function a(e){return"-"+e.toLowerCase()}function i(e,n,t,r,l){var o,u,c;if(null!=r)switch(m.call(r=r.valueOf())){case $:for(o=0;o<r.length;o++)i(e,n,t,r[o],l);break;case _:t=t&&t+"-";for(o in 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t&&(e._rule(),t=0),e.done(n)},atrule:function(n,r,l,a){t&&(e._rule(),t=0),e.atrule(n,r,l,a)},_atrule:function(n){t&&(e._rule(),t=0),e._atrule(n)},rule:function(n){n!==t&&(t&&e._rule(),e.rule(n),t=n)}}}function s(e){return":global("+e+")"}function f(e,n,t){return t={},t[e]=n,t}function p(e,n,t){if(arguments.length<3){var r=p.bind.apply(p,[null].concat([].slice.call(arguments,0)));return r.toString=function(){return"@"+e+" "+n},r}return f("@"+e+" "+n,t)}function h(){function n(n){if(!Z.length){_.push(function(e,n){return n?{init:$.init,decl:$.decl,done:$.done,err:$.err}:$});for(var t=0;t<2;t++)for(var r=_.length;r--;)Z[t]=v(e(_[r](Z[t],!!t),Z[t]))}return Z[n]}function t(e){return b.names[e]||(b.names[e]=e+b.suffix),b.names[e].match(/^\S+/)}function r(e,n,r,l,a){return n||r||l+t(a)}var a,h,$={init:function(){a=[],h=[]},done:function(e){if(0!=h.length)throw new Error("j2c error(s): "+JSON.stringify(h,null,2)+"in context:\n"+a.join(""));return 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dist/j2c.commonjs.js

@@ -12,5 +12,7 @@ 'use strict';
 var freeze = Object.freeze || function(o) {return o};
-function Default(target, source) {
+
+
+function defaults(target, source) {
   for (var k in source) if (own.call(source, k)) {
-    if (k.indexOf('$') && !(k in target)) target[k] = source[k]
+    if (k.indexOf('$') && !(k in target)) target[k] = source[k];
   }
@@ -21,6 +23,6 @@ return target
 function cartesian(a,b) {
-  var res = [], i, j
+  var res = [], i, j;
   for (j in b) if(own.call(b, j))
     for (i in a) if(own.call(a, i))
-      res.push(a[i] + b[j])
+      res.push(a[i] + b[j]);
   return res
@@ -34,3 +36,3 @@ }
 // regexp generated by scripts/regexps.js then trimmed by hand
-var selectorTokenizer = /[(),]|"(?:\\.|[^"\n])*"|'(?:\\.|[^'\n])*'|\/\*[\s\S]*?\*\//g
+var selectorTokenizer = /[(),]|"(?:\\.|[^"\n])*"|'(?:\\.|[^'\n])*'|\/\*[\s\S]*?\*\//g;
 
@@ -41,2 +43,3 @@
  * ignoring comas in strings, comments and in :pseudo-selectors(parameter, lists).
+ *
  * @param {string} selector
@@ -47,3 +50,3 @@ * @return {string[]}
 function splitSelector(selector) {
-  var indices = [], res = [], inParen = 0, o
+  var indices = [], res = [], inParen = 0, o;
   /*eslint-disable no-cond-assign*/
@@ -55,32 +58,32 @@ while (o = selectorTokenizer.exec(selector)) {
     case ')': inParen--; break
-    case ',': if (inParen) break; indices.push(o.index)
+    case ',': if (inParen) break; indices.push(o.index);
     }
   }
   for (o = indices.length; o--;){
-    res.unshift(selector.slice(indices[o] + 1))
-    selector = selector.slice(0, indices[o])
+    res.unshift(selector.slice(indices[o] + 1));
+    selector = selector.slice(0, indices[o]);
   }
-  res.unshift(selector)
+  res.unshift(selector);
   return res
 }
 
-// This is like the `selectorTokenizer`, but for the `&` operator
+// Like the `selectorTokenizer`, but for the `&` operator
+var ampersandTokenizer = /&|"(?:\\.|[^"\n])*"|'(?:\\.|[^'\n])*'|\/\*[\s\S]*?\*\//g;
 
-var ampersandTokenizer = /&|"(?:\\.|[^"\n])*"|'(?:\\.|[^'\n])*'|\/\*[\s\S]*?\*\//g
-
 function ampersand (selector, parents) {
-  var indices = [], split = [], res, o
+  var indices = [], split = [], res, o;
   /*eslint-disable no-cond-assign*/
   while (o = ampersandTokenizer.exec(selector)) {
   /*eslint-enable no-cond-assign*/
-    if (o[0] == '&') indices.push(o.index)
+    if (o[0] == '&') indices.push(o.index);
   }
   for (o = indices.length; o--;){
-    split.unshift(selector.slice(indices[o] + 1))
-    selector = selector.slice(0, indices[o])
+    split.unshift(selector.slice(indices[o] + 1));
+    selector = selector.slice(0, indices[o]);
   }
-  split.unshift(selector)
-  res = [split[0]]
+  split.unshift(selector);
+  if (split.length === 1) split.unshift('');
+  res = [split[0]];
   for (o = 1; o < split.length; o++) {
-    res = cartesian(res, cartesian(parents, [split[o]]))
+    res = cartesian(res, cartesian(parents, [split[o]]));
   }
@@ -92,4 +95,4 @@ return res.join(',')
   return function iter(arg) {
-    if (type.call(arg) === ARRAY) for (var i= 0 ; i < arg.length; i ++) iter(arg[i])
-    else f(arg)
+    if (type.call(arg) === ARRAY) for (var i= 0 ; i < arg.length; i ++) iter(arg[i]);
+    else f(arg);
   }
@@ -115,3 +118,3 @@ }
 function declarations(state, emit, prefix, o, local) {
-  var k, v, kk
+  var k, v, kk;
   if (o==null) return
@@ -123,3 +126,3 @@
 
-      declarations(state, emit, prefix, o[k], local)
+      declarations(state, emit, prefix, o[k], local);
 
@@ -130,9 +133,9 @@ break
     // of the declarations list.
-    prefix = (prefix && prefix + '-')
+    prefix = (prefix && prefix + '-');
     for (k in o) if (own.call(o, k)){
-      v = o[k]
+      v = o[k];
       if (/\$/.test(k)) {
         for (kk in (k = k.split('$'))) if (own.call(k, kk)) {
 
-          declarations(state, emit, prefix + k[kk], v, local)
+          declarations(state, emit, prefix + k[kk], v, local);
 
@@ -142,3 +145,3 @@ }
 
-        declarations(state, emit, prefix + k, v, local)
+        declarations(state, emit, prefix + k, v, local);
 
@@ -157,3 +160,3 @@ }
     // restore the dashes
-    k = prefix.replace(/_/g, '-').replace(/[A-Z]/g, decamelize)
+    k = prefix.replace(/_/g, '-').replace(/[A-Z]/g, decamelize);
 
@@ -165,8 +168,8 @@ if (local && (k == 'animation-name' || k == 'animation' || k == 'list-style')) {
 
-        return o.replace(/(var\([^)]+\))|:?global\(\s*([_A-Za-z][-\w]*)\s*\)|()(-?[_A-Za-z][-\w]*)/, state.L)
+        return o.replace(/^\s*(?:(var\([^)]+\))|:?global\(\s*([_A-Za-z][-\w]*)\s*\)|()(-?[_A-Za-z][-\w]*))/, state.localizeReplacer)
 
-      }).join(',')
+      }).join(',');
     }
 
-    emit.d(k, o)
+    emit.decl(k, o);
 
@@ -177,3 +180,3 @@ }
 /**
- * Hanldes at-rules
+ * Handles a single at-rules
  *
@@ -185,4 +188,8 @@ * @param {object} state - holds the localizer- and walker-related methods
  *                    if takes both parameters and a block.
- * @param {string} prefix - the current selector or the selector prefix
- *                          in case of nested rules
+ *                    k == [match, fullAtRule, atRuleType, params?]
+ *                    So in `@-webkit-keyframes foo`, we have
+ *                     - match = "@-webkit-keyframes foo"
+ *                     - fullAtRule = "@-webkit-keyframes"
+ *                     - atRuleType = "keyframes"
+ *                     - params = "foo"
  * @param {string|string[]|object|object[]} v - Either parameters for
@@ -192,11 +199,14 @@ *                                              block-less rules or
  *                                              for the others.
- * @param {string} inAtRule - are we nested in an at-rule?
+ * @param {string} prefix - the current selector or the selector prefix
+ *                          in case of nested rules
  * @param {boolean} local - are we in @local or in @global scope?
+ * @param {string} nestingDepth - are we nested in an at-rule or a selector?
  */
 
-function atRules(state, emit, k, v, prefix, local, inAtRule) {
+function atRules(state, emit, k, v, prefix, local, nestingDepth) {
 
-  for (var i = 0; i < state.$a.length; i++) {
+  // First iterate over user-provided at-rules and return if one of them corresponds to the current one
+  for (var i = 0; i < state.$atHandlers.length; i++) {
 
-    if (state.$a[i](state, emit, k, v, prefix, local, inAtRule)) return
+    if (state.$atHandlers[i](state, emit, k, v, prefix, local, nestingDepth)) return
 
@@ -206,3 +216,3 @@ }
   // using `/^global$/.test(k[2])` rather that 'global' == k[2] gzips
-  // slightly better because of the regexps test further down.
+  // slightly better thanks to the regexps tests further down.
   // It is slightly less efficient but this isn't a critical path.
@@ -212,3 +222,3 @@
 
-    rules(state, emit, prefix, v, 0, inAtRule)
+    rules(state, emit, prefix, v, 0, nestingDepth);
 
@@ -218,3 +228,3 @@
 
-    rules(state, emit, prefix, v, 1, inAtRule)
+    rules(state, emit, prefix, v, 1, nestingDepth);
 
@@ -224,19 +234,19 @@
 
-    if (!local || inAtRule) return emit.a('@-error-bad-at-adopt-placement' , JSON.stringify(k[0]), 0)
+    if (!local || nestingDepth) return emit.err('@adopt global or nested: ' + k[0])
 
-    if (!/^\.?[_A-Za-z][-\w]*$/.test(k[3])) return emit.a('@-error-bad-at-adopter', k[3], 0)
+    if (!/^\.?[_A-Za-z][-\w]*$/.test(k[3])) return emit.err('bad adopter ' + JSON.stringify(k[3]) + ' in ' + k[0])
 
-    i = []
+    i = [];
     flatIter(function(adoptee, asString) {
 
-      if(!/^\.?[_A-Za-z][-\w]*(?:\s+\.?[_A-Za-z][-\w]*)*$/.test(asString = adoptee.toString())) emit.a('@-error-bad-at-adoptee', JSON.stringify(adoptee), 0)
+      if(adoptee == null || !/^\.?[_A-Za-z][-\w]*(?:\s+\.?[_A-Za-z][-\w]*)*$/.test(asString = adoptee + '')) emit.err('bad adoptee '+ JSON.stringify(adoptee) + ' in ' + k[0]);
 
-      else i.push(asString.replace(/\./g, ''))
+      else i.push(asString.replace(/\./g, ''));
 
-    })(v)
+    })(v);
 
     // we may end up with duplicate classes but AFAIK it has no consequences on specificity.
     if (i.length) {
-      state.l(k[3] = k[3].replace(/\./g, ''))
-      state.n[k[3]] += (' ' + i.join(' '))
+      state.localize(k[3] = k[3].replace(/\./g, ''));
+      state.names[k[3]] += (' ' + i.join(' '));
     }
@@ -248,5 +258,5 @@
 
-      emit.a(k[0], v)
+      emit.atrule(k[1], k[2], v);
 
-    })(v)
+    })(v);
 
@@ -257,9 +267,9 @@
 
-      emit.a(k[1], '', 1)
+      emit.atrule(k[1], k[2], k[3], 1);
 
-      declarations(state, emit, '', v, local)
+      declarations(state, emit, '', v, local);
 
-      emit.A(k[1], '')
+      emit._atrule();
 
-    })(v)
+    })(v);
 
@@ -272,12 +282,12 @@ } else if (k[3] && /^(?:media|supports|page|keyframes)$/.test(k[2])) {
         /(var\([^)]+\))|:?global\(\s*([_A-Za-z][-\w]*)\s*\)|()(-?[_A-Za-z][-\w]*)/,
-        state.L
-      )
+        state.localizeReplacer
+      );
     }
 
 
-    emit.a(k[1], k[3], 1)
+    emit.atrule(k[1], k[2], k[3], 1);
 
     if ('page' == k[2]) {
 
-      declarations(state, emit, '', v, local)
+      declarations(state, emit, '', v, local);
 
@@ -289,12 +299,12 @@ } else {
         'keyframes' == k[2] ? '' : prefix,
-        v, local, 1
-      )
+        v, local, nestingDepth + 1
+      );
 
     }
 
-    emit.A(k[1], k[3])
+    emit._atrule();
 
   } else {
 
-    emit.a('@-error-unsupported-at-rule', JSON.stringify(k[0]))
+    emit.err('Unsupported at-rule: ' + k[0]);
 
@@ -312,7 +322,7 @@ }
  * @param {array|string|object} tree - a source object or sub-object.
- * @param {string} inAtRule - are we nested in an at-rule?
+ * @param {string} nestingDepth - are we nested in an at-rule?
  * @param {boolean} local - are we in @local or in @global scope?
  */
-function rules(state, emit, prefix, tree, local, inAtRule) {
-  var k, v, inDeclaration, kk
+function rules(state, emit, prefix, tree, local, nestingDepth) {
+  var k, v, inDeclaration, kk;
 
@@ -323,9 +333,9 @@ switch (type.call(tree)) {
     for (k in tree) if (own.call(tree, k)) {
-      v = tree[k]
+      v = tree[k];
 
       if (prefix.length > 0 && /^[-\w$]+$/.test(k)) {
         if (!inDeclaration) {
-          inDeclaration = 1
+          inDeclaration = 1;
 
-          emit.s(prefix)
+          emit.rule(prefix);
 
@@ -336,3 +346,3 @@ }
 
-            declarations(state, emit, k[kk], v, local)
+            declarations(state, emit, k[kk], v, local);
 
@@ -342,3 +352,3 @@ }
 
-          declarations(state, emit, k, v, local)
+          declarations(state, emit, k, v, local);
 
@@ -349,20 +359,20 @@ }
         // Handle At-rules
-        inDeclaration = 0
+        inDeclaration = 0;
 
         atRules(state, emit,
           /^(.(?:-[\w]+-)?([_A-Za-z][-\w]*))\b\s*(.*?)\s*$/.exec(k) || [k,'@','',''],
-          v, prefix, local, inAtRule
-        )
+          v, prefix, local, nestingDepth
+        );
 
       } else {
         // selector or nested sub-selectors
-        inDeclaration = 0
+        inDeclaration = 0;
 
         rules(
           state, emit,
-          // `prefix` ... Hefty. Ugly. Sadly necessary.
-          //
-          (prefix.length > 0 && (/,/.test(prefix) || /,/.test(k))) ?
+          // build the selector `prefix` for the next iteration.
+          // ugly and full of redundant bits but so far the fastest/shortest.gz
+          /*0 if*/(prefix.length > 0 && (/,/.test(prefix) || /,/.test(k))) ?
 
-            /*0*/ (kk = splitSelector(prefix), splitSelector(
+            /*0 then*/ (kk = splitSelector(prefix), splitSelector(
               local ?
@@ -372,3 +382,3 @@
                   /("(?:\\.|[^"\n])*"|'(?:\\.|[^'\n])*'|\/\*[\s\S]*?\*\/)|:global\(\s*(\.-?[_A-Za-z][-\w]*)\s*\)|(\.)(-?[_A-Za-z][-\w]*)/g,
-                  state.L
+                  state.localizeReplacer
                 ) :
@@ -383,5 +393,5 @@
 
-            /*0*/ /&/.test(k) ?
+            /*0 else*/ /*1 if*/ /&/.test(k) ?
 
-              /*1*/ ampersand(
+              /*1 then*/ ampersand(
                 local ?
@@ -391,3 +401,3 @@
                     /("(?:\\.|[^"\n])*"|'(?:\\.|[^'\n])*'|\/\*[\s\S]*?\*\/)|:global\(\s*(\.-?[_A-Za-z][-\w]*)\s*\)|(\.)(-?[_A-Za-z][-\w]*)/g,
-                    state.L
+                    state.localizeReplacer
                   ) :
@@ -399,3 +409,3 @@
 
-              /*1*/ prefix + (
+              /*1 else*/ prefix + (
                 local ?
@@ -405,3 +415,3 @@
                     /("(?:\\.|[^"\n])*"|'(?:\\.|[^'\n])*'|\/\*[\s\S]*?\*\/)|:global\(\s*(\.-?[_A-Za-z][-\w]*)\s*\)|(\.)(-?[_A-Za-z][-\w]*)/g,
-                    state.L
+                    state.localizeReplacer
                   ) :
@@ -411,4 +421,4 @@
                 ),
-           v, local, inAtRule
-        )
+           v, local, nestingDepth + 1
+        );
 
@@ -423,3 +433,3 @@ }
 
-      rules(state, emit, prefix, tree[k], local, inAtRule)
+      rules(state, emit, prefix, tree[k], local, nestingDepth);
 
@@ -431,7 +441,7 @@ }
     // CSS hacks or ouptut of `j2c.inline`.
+    if (!prefix.length) emit.err('No selector');
+    emit.rule(prefix || ' ');
 
-    emit.s(prefix.length > 0 ? prefix : ':-error-no-selector')
+    declarations(state, emit, '', tree, local);
 
-    declarations(state, emit, '', tree, local)
-
   }
@@ -447,28 +457,27 @@ }
 // contains arrays.
-// There's no `S` handler, because the core compiler never
+// There's no `_rule` handler, because the core compiler never
 // calls it.
 function closeSelectors(next, inline) {
-  var lastSelector
+  var lastSelector;
   return inline ? next : {
-    i: function(){lastSelector = 0; next.i()},
-    x: function (raw) {
-      if (lastSelector) {next.S(); lastSelector = 0}
-      return next.x(raw)
+    init: function(){lastSelector = 0; next.init();},
+    done: function (raw) {
+      if (lastSelector) {next._rule(); lastSelector = 0;}
+      return next.done(raw)
     },
-    a: function (rule, param, takesBlock) {
-      if (lastSelector) {next.S(); lastSelector = 0}
-      next.a(rule, param, takesBlock)
+    atrule: function (rule, kind, param, takesBlock) {
+      if (lastSelector) {next._rule(); lastSelector = 0;}
+      next.atrule(rule, kind, param, takesBlock);
     },
-    A: function (rule) {
-      if (lastSelector) {next.S(); lastSelector = 0}
-      next.A(rule)
+    _atrule: function (rule) {
+      if (lastSelector) {next._rule(); lastSelector = 0;}
+      next._atrule(rule);
     },
-    s: function (selector) {
+    rule: function (selector) {
       if (selector !== lastSelector){
-        if (lastSelector) next.S()
-        next.s(selector)
-        lastSelector = selector
+        if (lastSelector) next._rule();
+        next.rule(selector);
+        lastSelector = selector;
       }
-    },
-    d: next.d
+    }
   }
@@ -482,4 +491,4 @@ }
 function kv (k, v, o) {
-  o = {}
-  o[k] = v
+  o = {};
+  o[k] = v;
   return o
@@ -493,5 +502,5 @@ }
     // inner curry!
-    var _at = at.bind.apply(at, [null].concat([].slice.call(arguments,0)))
+    var _at = at.bind.apply(at, [null].concat([].slice.call(arguments,0)));
     // So that it can be used as a key in an ES6 object literal.
-    _at.toString = function(){return '@' + rule + ' ' + params}
+    _at.toString = function(){return '@' + rule + ' ' + params};
     return _at
@@ -504,28 +513,32 @@ }
 
-  // palceholder for the buffer used by the `$sink` handlers
-  var buf
+  // the buffer that accumulates the output. Initialized in `$sink.i()`
+  var buf, err;
 
   // the bottom of the 'codegen' stream. Mirrors the `$filter` plugin API.
   var $sink = {
-    // Init
-    i: function(){buf=[]},
-    // done (eXit)
-    x: function (raw) {return raw ? buf : buf.join('')},
-    // start At-rule
-    a: function (rule, argument, takesBlock) {
-      buf.push(rule, argument && ' ',argument, takesBlock ? ' {\n' : ';\n')
+    init: function(){buf=[], err=[];},
+    done: function (raw) {
+      if (err.length != 0) throw new Error('j2c error(s): ' + JSON.stringify(err,null,2) + 'in context:\n' + buf.join(''))
+      return raw ? buf : buf.join('')
     },
-    // end At-rule
-    A: function ()            {buf.push('}\n')},
-    // start Selector
-    s: function (selector)    {buf.push(selector, ' {\n')},
-    // end Selector
-    S: function ()            {buf.push('}\n')},
-    // declarations
-    d: function (prop, value) {buf.push(prop, prop && ':', value, ';\n')}
-  }
+    err: function(msg) {
+      err.push(msg);
+      buf.push('/* +++ ERROR +++ ' + msg + ' */\n');
+    },
+    atrule: function (rule, kind, param, takesBlock) {
+      buf.push(rule, param && ' ', param, takesBlock ? ' {' : ';', _instance.endline);
+    },
+    // close atrule
+    _atrule: function () {buf.push('}', _instance.endline);},
+    rule: function (selector) {buf.push(selector, ' {', _instance.endline);},
+    // close rule
+    _rule: function () {buf.push('}', _instance.endline);},
+    decl: function (prop, value) {buf.push(prop, prop && ':', value, ';', _instance.endline);}
+  };
 
-  var $filters = [closeSelectors]
-  var $atHandlers = []
+  // holds the `$filter` and `$at` handlers
+  var $filters = [closeSelectors];
+  var $atHandlers = [];
 
+  // the public API (see the main docs)
   var _instance = {
@@ -536,3 +549,5 @@ at: at,
     names: {},
+    endline: '\n',
     suffix: '__j2c-' +
+      // 128 bits of randomness
       Math.floor(Math.random() * 0x100000000).toString(36) + '-' +
@@ -542,13 +557,32 @@ Math.floor(Math.random() * 0x100000000).toString(36) + '-' +
       Math.floor(Math.random() * 0x100000000).toString(36),
-    use: function() {
-      _use(emptyArray.slice.call(arguments))
-      return _instance
+    $plugins: [],
+    sheet: function(tree) {
+      var emit = _createOrRetrieveStream(0);
+      emit.init();
+      rules(
+        _walkers[0],
+        emit,
+        '', // prefix
+        tree,
+        1,  // local, by default
+        0   // nesting depth
+      );
+
+      return emit.done()
     },
-    $plugins: []
-  }
+    inline: function (tree, options) {
+      var emit = _createOrRetrieveStream(1);
+      emit.init();
+      declarations(
+        _walkers[1],
+        emit,
+        '', // prefix
+        tree,
+        !(options && options.global)   // local, by default
+      );
+      return emit.done()
+    }
+  };
 
-  var _streams = []
-
-  // The `state` (for the core) / `walker` (for the plugins) tables.
-
+  // The `state` (for the core functions) / `walker` (for the plugins) tables.
   var _walkers = [
@@ -558,51 +592,21 @@ // for j2c.sheet
       // helpers for locaizing class and animation names
-      L: _localizeReplacer, // second argument to String.prototype.replace
-      l: _localize,         // mangles local names
-      n: _instance.names,    // local => mangled mapping
-      $a: $atHandlers,      // extra at-rules
+      localizeReplacer: _localizeReplacer, // second argument to String.prototype.replace
+      localize: _localize,                 // mangles local names
+      names: _instance.names,              // local => mangled mapping
+      $atHandlers: $atHandlers,            // extra at-rules
       // The core walker methods, to be provided to plugins
-      a: atRules,
-      d: declarations,
-      r: rules
+      atrule: atRules,
+      decl: declarations,
+      rule: rules
     },
     // likewise, for j2c.inline (idem with `$a`, `a` and `s` removed)
     {
-      L: _localizeReplacer,
-      l: _localize,
-      n: _instance.names,
-      d: declarations
+      localizeReplacer: _localizeReplacer,
+      localize: _localize,
+      names: _instance.names,
+      decl: declarations
     }
-  ]
+  ];
 
 
-  // The main API functions
-
-  _instance.sheet = function(tree) {
-    var emit = _getStream(0)
-    emit.i()
-    rules(
-      _walkers[0],
-      emit,
-      '',    // prefix
-      tree,
-      1,      // local, by default
-      0     // inAtRule
-    )
-
-    return emit.x()
-  }
-
-  _instance.inline = function (tree) {
-    var emit = _getStream(1)
-    emit.i()
-    declarations(
-      _walkers[1],
-      emit,
-      '',         // prefix
-      tree,
-      1           //local
-    )
-    return emit.x()
-  }
-
   // inner helpers
@@ -617,5 +621,5 @@
 
-    _instance.$plugins.push(plugin)
+    _instance.$plugins.push(plugin);
 
-    if (type.call(plugin) === FUNCTION) plugin = plugin(_instance)
+    if (type.call(plugin) === FUNCTION) plugin = plugin(_instance);
 
@@ -625,50 +629,74 @@ if (!plugin) return
     flatIter(function(filter) {
-      $filters.push(filter)
-    })(plugin.$filter || emptyArray)
+      $filters.push(filter);
+    })(plugin.$filter || emptyArray);
 
     flatIter(function(handler) {
-      $atHandlers.push(handler)
-    })(plugin.$at || emptyArray)
+      $atHandlers.push(handler);
+    })(plugin.$at || emptyArray);
 
-    Default(_instance.names, plugin.$names || emptyObject)
+    defaults(_instance.names, plugin.$names || emptyObject);
 
-    _use(plugin.$plugins || emptyArray)
+    _use(plugin.$plugins || emptyArray);
 
-    $sink = plugin.$sink || $sink
+    $sink = plugin.$sink || $sink;
 
-    Default(_instance, plugin)
-  })
+    defaults(_instance, plugin);
+  });
 
-  function _getStream(inline) {
+
+  var _streams = [];
+  /**
+   * returns the codegen streams, creating them if necessary
+   * @param
+   */
+  function _createOrRetrieveStream(inline) {
+    // build the stream processors if needed
     if (!_streams.length) {
-      for(var i = 0; i < 2; i++){
-        $filters[$filters.length - i] = function(_, inline) {return inline ? {i:$sink.i, d:$sink.d, x:$sink.x} : $sink}
+      // append the $sink as the ultimate filter
+      $filters.push(function(_, inline) {return inline ? {init:$sink.init, decl:$sink.decl, done:$sink.done, err: $sink.err} : $sink});
+      for(var i = 0; i < 2; i++){ // 0 for j2c.sheet, 1 for j2c.inline
         for (var j = $filters.length; j--;) {
-          _streams[i] = freeze(Default(
-            $filters[j](_streams[i], !!i, _walkers[i]),
-            _streams[i]
-          ))
+          _streams[i] = freeze(
+            defaults(
+              $filters[j](_streams[i], !!i),
+              _streams[i]
+            )
+          );
         }
       }
     }
-    var res = _streams[inline]
-    return res
+    return _streams[inline]
   }
 
+  /**
+   * Returns a localized version of a given name.
+   * Registers the pair in `instnace.name` if needed.
+   *
+   * @param {string} name - the name to localize
+   * @return {string} - the localized version
+   */
   function _localize(name) {
-    if (!_instance.names[name]) _instance.names[name] = name + _instance.suffix
+    if (!_instance.names[name]) _instance.names[name] = name + _instance.suffix;
     return _instance.names[name].match(/^\S+/)
   }
 
-  function _localizeReplacer(match, string, global, dot, name) {
-    if (string || global) return string || global
-    return dot + _localize(name)
+  /**
+   * Used as second argument for str.replace(localizeRegex, replacer)
+   * `ignore`, `global` and `(dot, name)` are mutually exclusive
+   *
+   * @param {string} match - the whole match (ignored)
+   * @param {string|null} ignore - a comment or a string literal
+   * @param {string|null} global - a global name
+   * @param {string|null} dot - either '.' for a local class name or the empty string otherwise
+   * @param {string|null} name - the name to localize
+   * @return {string}
+   */
+  function _localizeReplacer(match, ignore, global$$1, dot, name) {
+    return ignore || global$$1 || dot + _localize(name)
   }
 
+  _use(emptyArray.slice.call(arguments));
   return _instance
 }
 
-var _j2c = j2c()
-'sheet|inline|names|at|global|kv|suffix'.split('|').map(function(m){j2c[m] = _j2c[m]})
-
-module.exports = j2c;
+module.exports = j2c;

dist/j2c.commonjs.min.js

@@ -1,1 +0,1 @@
-"use strict";function Default(e,t){for(var n in t)own.call(t,n)&&(!n.indexOf("$")||n in e||(e[n]=t[n]));return e}function cartesian(e,t){var n,a,r=[];for(a in t)if(own.call(t,a))for(n in e)own.call(e,n)&&r.push(e[n]+t[a]);return r}function splitSelector(e){for(var t,n=[],a=[],r=0;t=selectorTokenizer.exec(e);)switch(t[0]){case"(":r++;break;case")":r--;break;case",":if(r)break;n.push(t.index)}for(t=n.length;t--;)a.unshift(e.slice(n[t]+1)),e=e.slice(0,n[t]);return a.unshift(e),a}function ampersand(e,t){for(var n,a,r=[],l=[];a=ampersandTokenizer.exec(e);)"&"==a[0]&&r.push(a.index);for(a=r.length;a--;)l.unshift(e.slice(r[a]+1)),e=e.slice(0,r[a]);for(l.unshift(e),n=[l[0]],a=1;a<l.length;a++)n=cartesian(n,cartesian(t,[l[a]]));return n.join(",")}function flatIter(e){return function t(n){if(type.call(n)===ARRAY)for(var a=0;a<n.length;a++)t(n[a]);else e(n)}}function decamelize(e){return"-"+e.toLowerCase()}function declarations(e,t,n,a,r){var l,i,s;if(null!=a)switch(type.call(a=a.valueOf())){case ARRAY:for(l=0;l<a.length;l++)declarations(e,t,n,a[l],r);break;case OBJECT:n=n&&n+"-";for(l in a)if(own.call(a,l))if(i=a[l],/\$/.test(l))for(s in l=l.split("$"))own.call(l,s)&&declarations(e,t,n+l[s],i,r);else declarations(e,t,n+l,i,r);break;default:l=n.replace(/_/g,"-").replace(/[A-Z]/g,decamelize),!r||"animation-name"!=l&&"animation"!=l&&"list-style"!=l||(a=a.split(",").map(function(t){return t.replace(/(var\([^)]+\))|:?global\(\s*([_A-Za-z][-\w]*)\s*\)|()(-?[_A-Za-z][-\w]*)/,e.L)}).join(",")),t.d(l,a)}}function atRules(e,t,n,a,r,l,i){for(var s=0;s<e.$a.length;s++)if(e.$a[s](e,t,n,a,r,l,i))return;if(!n[3]&&/^global$/.test(n[2]))rules(e,t,r,a,0,i);else if(!n[3]&&/^local$/.test(n[2]))rules(e,t,r,a,1,i);else if(n[3]&&/^adopt$/.test(n[2])){if(!l||i)return t.a("@-error-bad-at-adopt-placement",JSON.stringify(n[0]),0);if(!/^\.?[_A-Za-z][-\w]*$/.test(n[3]))return t.a("@-error-bad-at-adopter",n[3],0);s=[],flatIter(function(e,n){/^\.?[_A-Za-z][-\w]*(?:\s+\.?[_A-Za-z][-\w]*)*$/.test(n=e.toString())?s.push(n.replace(/\./g,"")):t.a("@-error-bad-at-adoptee",JSON.stringify(e),0)})(a),s.length&&(e.l(n[3]=n[3].replace(/\./g,"")),e.n[n[3]]+=" "+s.join(" "))}else!n[3]&&/^(?:namespace|import|charset)$/.test(n[2])?flatIter(function(e){t.a(n[0],e)})(a):!n[3]&&/^(?:font-face|viewport)$/.test(n[2])?flatIter(function(a){t.a(n[1],"",1),declarations(e,t,"",a,l),t.A(n[1],"")})(a):n[3]&&/^(?:media|supports|page|keyframes)$/.test(n[2])?(l&&"keyframes"==n[2]&&(n[3]=n[3].replace(/(var\([^)]+\))|:?global\(\s*([_A-Za-z][-\w]*)\s*\)|()(-?[_A-Za-z][-\w]*)/,e.L)),t.a(n[1],n[3],1),"page"==n[2]?declarations(e,t,"",a,l):rules(e,t,"keyframes"==n[2]?"":r,a,l,1),t.A(n[1],n[3])):t.a("@-error-unsupported-at-rule",JSON.stringify(n[0]))}function rules(e,t,n,a,r,l){var i,s,o,c;switch(type.call(a)){case OBJECT:for(i in a)if(own.call(a,i))if(s=a[i],n.length>0&&/^[-\w$]+$/.test(i))if(o||(o=1,t.s(n)),/\$/.test(i))for(c in i=i.split("$"))own.call(i,c)&&declarations(e,t,i[c],s,r);else declarations(e,t,i,s,r);else/^@/.test(i)?(o=0,atRules(e,t,/^(.(?:-[\w]+-)?([_A-Za-z][-\w]*))\b\s*(.*?)\s*$/.exec(i)||[i,"@","",""],s,n,r,l)):(o=0,rules(e,t,n.length>0&&(/,/.test(n)||/,/.test(i))?(c=splitSelector(n),splitSelector(r?i.replace(/("(?:\\.|[^"\n])*"|'(?:\\.|[^'\n])*'|\/\*[\s\S]*?\*\/)|:global\(\s*(\.-?[_A-Za-z][-\w]*)\s*\)|(\.)(-?[_A-Za-z][-\w]*)/g,e.L):i).map(function(e){return/&/.test(e)?ampersand(e,c):c.map(function(t){return t+e}).join(",")}).join(",")):/&/.test(i)?ampersand(r?i.replace(/("(?:\\.|[^"\n])*"|'(?:\\.|[^'\n])*'|\/\*[\s\S]*?\*\/)|:global\(\s*(\.-?[_A-Za-z][-\w]*)\s*\)|(\.)(-?[_A-Za-z][-\w]*)/g,e.L):i,[n]):n+(r?i.replace(/("(?:\\.|[^"\n])*"|'(?:\\.|[^'\n])*'|\/\*[\s\S]*?\*\/)|:global\(\s*(\.-?[_A-Za-z][-\w]*)\s*\)|(\.)(-?[_A-Za-z][-\w]*)/g,e.L):i),s,r,l));break;case ARRAY:for(i=0;i<a.length;i++)rules(e,t,n,a[i],r,l);break;case STRING:t.s(n.length>0?n:":-error-no-selector"),declarations(e,t,"",a,r)}}function closeSelectors(e,t){var n;return t?e:{i:function(){n=0,e.i()},x:function(t){return n&&(e.S(),n=0),e.x(t)},a:function(t,a,r){n&&(e.S(),n=0),e.a(t,a,r)},A:function(t){n&&(e.S(),n=0),e.A(t)},s:function(t){t!==n&&(n&&e.S(),e.s(t),n=t)},d:e.d}}function global(e){return":global("+e+")"}function kv(e,t,n){return n={},n[e]=t,n}function at(e,t,n){if(arguments.length<3){var a=at.bind.apply(at,[null].concat([].slice.call(arguments,0)));return a.toString=function(){return"@"+e+" "+t},a}return kv("@"+e+" "+t,n)}function j2c(){function e(e){if(!o.length)for(var t=0;2>t;t++){l[l.length-t]=function(e,t){return t?{i:r.i,d:r.d,x:r.x}:r};for(var n=l.length;n--;)o[t]=freeze(Default(l[n](o[t],!!t,c[t]),o[t]))}var a=o[e];return a}function t(e){return s.names[e]||(s.names[e]=e+s.suffix),s.names[e].match(/^\S+/)}function n(e,n,a,r,l){return n||a?n||a:r+t(l)}var a,r={i:function(){a=[]},x:function(e){return e?a:a.join("")},a:function(e,t,n){a.push(e,t&&" ",t,n?" {\n":";\n")},A:function(){a.push("}\n")},s:function(e){a.push(e," {\n")},S:function(){a.push("}\n")},d:function(e,t){a.push(e,e&&":",t,";\n")}},l=[closeSelectors],i=[],s={at:at,global:global,kv:kv,names:{},suffix:"__j2c-"+Math.floor(4294967296*Math.random()).toString(36)+"-"+Math.floor(4294967296*Math.random()).toString(36)+"-"+Math.floor(4294967296*Math.random()).toString(36)+"-"+Math.floor(4294967296*Math.random()).toString(36),use:function(){return u(emptyArray.slice.call(arguments)),s},$plugins:[]},o=[],c=[{L:n,l:t,n:s.names,$a:i,a:atRules,d:declarations,r:rules},{L:n,l:t,n:s.names,d:declarations}];s.sheet=function(t){var n=e(0);return n.i(),rules(c[0],n,"",t,1,0),n.x()},s.inline=function(t){var n=e(1);return n.i(),declarations(c[1],n,"",t,1),n.x()};var u=flatIter(function(e){~s.$plugins.indexOf(e)||(s.$plugins.push(e),type.call(e)===FUNCTION&&(e=e(s)),e&&(flatIter(function(e){l.push(e)})(e.$filter||emptyArray),flatIter(function(e){i.push(e)})(e.$at||emptyArray),Default(s.names,e.$names||emptyObject),u(e.$plugins||emptyArray),r=e.$sink||r,Default(s,e)))});return s}var emptyArray=[],emptyObject={},type=emptyObject.toString,ARRAY=type.call(emptyArray),OBJECT=type.call(emptyObject),STRING=type.call(""),FUNCTION=type.call(type),own=emptyObject.hasOwnProperty,freeze=Object.freeze||function(e){return e},selectorTokenizer=/[(),]|"(?:\\.|[^"\n])*"|'(?:\\.|[^'\n])*'|\/\*[\s\S]*?\*\//g,ampersandTokenizer=/&|"(?:\\.|[^"\n])*"|'(?:\\.|[^'\n])*'|\/\*[\s\S]*?\*\//g,_j2c=j2c();"sheet|inline|names|at|global|kv|suffix".split("|").map(function(e){j2c[e]=_j2c[e]}),module.exports=j2c;
+"use strict";function defaults(e,t){for(var n in t)own.call(t,n)&&(!n.indexOf("$")||n in e||(e[n]=t[n]));return e}function cartesian(e,t){var n,r,a=[];for(r in t)if(own.call(t,r))for(n in e)own.call(e,n)&&a.push(e[n]+t[r]);return a}function splitSelector(e){for(var t,n=[],r=[],a=0;t=selectorTokenizer.exec(e);)switch(t[0]){case"(":a++;break;case")":a--;break;case",":if(a)break;n.push(t.index)}for(t=n.length;t--;)r.unshift(e.slice(n[t]+1)),e=e.slice(0,n[t]);return r.unshift(e),r}function ampersand(e,t){for(var n,r,a=[],l=[];r=ampersandTokenizer.exec(e);)"&"==r[0]&&a.push(r.index);for(r=a.length;r--;)l.unshift(e.slice(a[r]+1)),e=e.slice(0,a[r]);for(l.unshift(e),1===l.length&&l.unshift(""),n=[l[0]],r=1;r<l.length;r++)n=cartesian(n,cartesian(t,[l[r]]));return n.join(",")}function flatIter(e){return function t(n){if(type.call(n)===ARRAY)for(var r=0;r<n.length;r++)t(n[r]);else e(n)}}function decamelize(e){return"-"+e.toLowerCase()}function declarations(e,t,n,r,a){var l,i,o;if(null!=r)switch(type.call(r=r.valueOf())){case ARRAY:for(l=0;l<r.length;l++)declarations(e,t,n,r[l],a);break;case OBJECT:n=n&&n+"-";for(l in r)if(own.call(r,l))if(i=r[l],/\$/.test(l))for(o in l=l.split("$"))own.call(l,o)&&declarations(e,t,n+l[o],i,a);else declarations(e,t,n+l,i,a);break;default:l=n.replace(/_/g,"-").replace(/[A-Z]/g,decamelize),!a||"animation-name"!=l&&"animation"!=l&&"list-style"!=l||(r=r.split(",").map(function(t){return t.replace(/^\s*(?:(var\([^)]+\))|:?global\(\s*([_A-Za-z][-\w]*)\s*\)|()(-?[_A-Za-z][-\w]*))/,e.localizeReplacer)}).join(",")),t.decl(l,r)}}function atRules(e,t,n,r,a,l,i){for(var o=0;o<e.$atHandlers.length;o++)if(e.$atHandlers[o](e,t,n,r,a,l,i))return;if(!n[3]&&/^global$/.test(n[2]))rules(e,t,a,r,0,i);else if(!n[3]&&/^local$/.test(n[2]))rules(e,t,a,r,1,i);else if(n[3]&&/^adopt$/.test(n[2])){if(!l||i)return t.err("@adopt global or nested: "+n[0]);if(!/^\.?[_A-Za-z][-\w]*$/.test(n[3]))return t.err("bad adopter "+JSON.stringify(n[3])+" in "+n[0]);o=[],flatIter(function(e,r){null!=e&&/^\.?[_A-Za-z][-\w]*(?:\s+\.?[_A-Za-z][-\w]*)*$/.test(r=e+"")?o.push(r.replace(/\./g,"")):t.err("bad adoptee "+JSON.stringify(e)+" in "+n[0])})(r),o.length&&(e.localize(n[3]=n[3].replace(/\./g,"")),e.names[n[3]]+=" "+o.join(" "))}else!n[3]&&/^(?:namespace|import|charset)$/.test(n[2])?flatIter(function(e){t.atrule(n[1],n[2],e)})(r):!n[3]&&/^(?:font-face|viewport)$/.test(n[2])?flatIter(function(r){t.atrule(n[1],n[2],n[3],1),declarations(e,t,"",r,l),t._atrule()})(r):n[3]&&/^(?:media|supports|page|keyframes)$/.test(n[2])?(l&&"keyframes"==n[2]&&(n[3]=n[3].replace(/(var\([^)]+\))|:?global\(\s*([_A-Za-z][-\w]*)\s*\)|()(-?[_A-Za-z][-\w]*)/,e.localizeReplacer)),t.atrule(n[1],n[2],n[3],1),"page"==n[2]?declarations(e,t,"",r,l):rules(e,t,"keyframes"==n[2]?"":a,r,l,i+1),t._atrule()):t.err("Unsupported at-rule: "+n[0])}function rules(e,t,n,r,a,l){var i,o,s,c;switch(type.call(r)){case OBJECT:for(i in r)if(own.call(r,i))if(o=r[i],n.length>0&&/^[-\w$]+$/.test(i))if(s||(s=1,t.rule(n)),/\$/.test(i))for(c in i=i.split("$"))own.call(i,c)&&declarations(e,t,i[c],o,a);else declarations(e,t,i,o,a);else/^@/.test(i)?(s=0,atRules(e,t,/^(.(?:-[\w]+-)?([_A-Za-z][-\w]*))\b\s*(.*?)\s*$/.exec(i)||[i,"@","",""],o,n,a,l)):(s=0,rules(e,t,n.length>0&&(/,/.test(n)||/,/.test(i))?(c=splitSelector(n),splitSelector(a?i.replace(/("(?:\\.|[^"\n])*"|'(?:\\.|[^'\n])*'|\/\*[\s\S]*?\*\/)|:global\(\s*(\.-?[_A-Za-z][-\w]*)\s*\)|(\.)(-?[_A-Za-z][-\w]*)/g,e.localizeReplacer):i).map(function(e){return/&/.test(e)?ampersand(e,c):c.map(function(t){return t+e}).join(",")}).join(",")):/&/.test(i)?ampersand(a?i.replace(/("(?:\\.|[^"\n])*"|'(?:\\.|[^'\n])*'|\/\*[\s\S]*?\*\/)|:global\(\s*(\.-?[_A-Za-z][-\w]*)\s*\)|(\.)(-?[_A-Za-z][-\w]*)/g,e.localizeReplacer):i,[n]):n+(a?i.replace(/("(?:\\.|[^"\n])*"|'(?:\\.|[^'\n])*'|\/\*[\s\S]*?\*\/)|:global\(\s*(\.-?[_A-Za-z][-\w]*)\s*\)|(\.)(-?[_A-Za-z][-\w]*)/g,e.localizeReplacer):i),o,a,l+1));break;case ARRAY:for(i=0;i<r.length;i++)rules(e,t,n,r[i],a,l);break;case STRING:n.length||t.err("No selector"),t.rule(n||" "),declarations(e,t,"",r,a)}}function closeSelectors(e,t){var n;return t?e:{init:function(){n=0,e.init()},done:function(t){return n&&(e._rule(),n=0),e.done(t)},atrule:function(t,r,a,l){n&&(e._rule(),n=0),e.atrule(t,r,a,l)},_atrule:function(t){n&&(e._rule(),n=0),e._atrule(t)},rule:function(t){t!==n&&(n&&e._rule(),e.rule(t),n=t)}}}function global(e){return":global("+e+")"}function kv(e,t,n){return n={},n[e]=t,n}function at(e,t,n){if(arguments.length<3){var r=at.bind.apply(at,[null].concat([].slice.call(arguments,0)));return r.toString=function(){return"@"+e+" "+t},r}return kv("@"+e+" "+t,n)}function j2c(){function e(e){if(!f.length){i.push(function(e,t){return t?{init:l.init,decl:l.decl,done:l.done,err:l.err}:l});for(var t=0;t<2;t++)for(var n=i.length;n--;)f[t]=freeze(defaults(i[n](f[t],!!t),f[t]))}return f[e]}function t(e){return s.names[e]||(s.names[e]=e+s.suffix),s.names[e].match(/^\S+/)}function n(e,n,r,a,l){return n||r||a+t(l)}var r,a,l={init:function(){r=[],a=[]},done:function(e){if(0!=a.length)throw new Error("j2c error(s): "+JSON.stringify(a,null,2)+"in context:\n"+r.join(""));return e?r:r.join("")},err:function(e){a.push(e),r.push("/* +++ ERROR +++ "+e+" */\n")},atrule:function(e,t,n,a){r.push(e,n&&" ",n,a?" {":";",s.endline)},_atrule:function(){r.push("}",s.endline)},rule:function(e){r.push(e," {",s.endline)},_rule:function(){r.push("}",s.endline)},decl:function(e,t){r.push(e,e&&":",t,";",s.endline)}},i=[closeSelectors],o=[],s={at:at,global:global,kv:kv,names:{},endline:"\n",suffix:"__j2c-"+Math.floor(4294967296*Math.random()).toString(36)+"-"+Math.floor(4294967296*Math.random()).toString(36)+"-"+Math.floor(4294967296*Math.random()).toString(36)+"-"+Math.floor(4294967296*Math.random()).toString(36),$plugins:[],sheet:function(t){var n=e(0);return n.init(),rules(c[0],n,"",t,1,0),n.done()},inline:function(t,n){var r=e(1);return r.init(),declarations(c[1],r,"",t,!(n&&n.global)),r.done()}},c=[{localizeReplacer:n,localize:t,names:s.names,$atHandlers:o,atrule:atRules,decl:declarations,rule:rules},{localizeReplacer:n,localize:t,names:s.names,decl:declarations}],u=flatIter(function(e){~s.$plugins.indexOf(e)||(s.$plugins.push(e),type.call(e)===FUNCTION&&(e=e(s)),e&&(flatIter(function(e){i.push(e)})(e.$filter||emptyArray),flatIter(function(e){o.push(e)})(e.$at||emptyArray),defaults(s.names,e.$names||emptyObject),u(e.$plugins||emptyArray),l=e.$sink||l,defaults(s,e)))}),f=[];return u(emptyArray.slice.call(arguments)),s}var emptyArray=[],emptyObject={},type=emptyObject.toString,ARRAY=type.call(emptyArray),OBJECT=type.call(emptyObject),STRING=type.call(""),FUNCTION=type.call(type),own=emptyObject.hasOwnProperty,freeze=Object.freeze||function(e){return e},selectorTokenizer=/[(),]|"(?:\\.|[^"\n])*"|'(?:\\.|[^'\n])*'|\/\*[\s\S]*?\*\//g,ampersandTokenizer=/&|"(?:\\.|[^"\n])*"|'(?:\\.|[^'\n])*'|\/\*[\s\S]*?\*\//g;module.exports=j2c;

dist/j2c.es6.js

@@ -10,5 +10,7 @@ var emptyArray = [];
 var freeze = Object.freeze || function(o) {return o};
-function Default(target, source) {
+
+
+function defaults(target, source) {
   for (var k in source) if (own.call(source, k)) {
-    if (k.indexOf('$') && !(k in target)) target[k] = source[k]
+    if (k.indexOf('$') && !(k in target)) target[k] = source[k];
   }
@@ -19,6 +21,6 @@ return target
 function cartesian(a,b) {
-  var res = [], i, j
+  var res = [], i, j;
   for (j in b) if(own.call(b, j))
     for (i in a) if(own.call(a, i))
-      res.push(a[i] + b[j])
+      res.push(a[i] + b[j]);
   return res
@@ -32,3 +34,3 @@ }
 // regexp generated by scripts/regexps.js then trimmed by hand
-var selectorTokenizer = /[(),]|"(?:\\.|[^"\n])*"|'(?:\\.|[^'\n])*'|\/\*[\s\S]*?\*\//g
+var selectorTokenizer = /[(),]|"(?:\\.|[^"\n])*"|'(?:\\.|[^'\n])*'|\/\*[\s\S]*?\*\//g;
 
@@ -39,2 +41,3 @@
  * ignoring comas in strings, comments and in :pseudo-selectors(parameter, lists).
+ *
  * @param {string} selector
@@ -45,3 +48,3 @@ * @return {string[]}
 function splitSelector(selector) {
-  var indices = [], res = [], inParen = 0, o
+  var indices = [], res = [], inParen = 0, o;
   /*eslint-disable no-cond-assign*/
@@ -53,32 +56,32 @@ while (o = selectorTokenizer.exec(selector)) {
     case ')': inParen--; break
-    case ',': if (inParen) break; indices.push(o.index)
+    case ',': if (inParen) break; indices.push(o.index);
     }
   }
   for (o = indices.length; o--;){
-    res.unshift(selector.slice(indices[o] + 1))
-    selector = selector.slice(0, indices[o])
+    res.unshift(selector.slice(indices[o] + 1));
+    selector = selector.slice(0, indices[o]);
   }
-  res.unshift(selector)
+  res.unshift(selector);
   return res
 }
 
-// This is like the `selectorTokenizer`, but for the `&` operator
+// Like the `selectorTokenizer`, but for the `&` operator
+var ampersandTokenizer = /&|"(?:\\.|[^"\n])*"|'(?:\\.|[^'\n])*'|\/\*[\s\S]*?\*\//g;
 
-var ampersandTokenizer = /&|"(?:\\.|[^"\n])*"|'(?:\\.|[^'\n])*'|\/\*[\s\S]*?\*\//g
-
 function ampersand (selector, parents) {
-  var indices = [], split = [], res, o
+  var indices = [], split = [], res, o;
   /*eslint-disable no-cond-assign*/
   while (o = ampersandTokenizer.exec(selector)) {
   /*eslint-enable no-cond-assign*/
-    if (o[0] == '&') indices.push(o.index)
+    if (o[0] == '&') indices.push(o.index);
   }
   for (o = indices.length; o--;){
-    split.unshift(selector.slice(indices[o] + 1))
-    selector = selector.slice(0, indices[o])
+    split.unshift(selector.slice(indices[o] + 1));
+    selector = selector.slice(0, indices[o]);
   }
-  split.unshift(selector)
-  res = [split[0]]
+  split.unshift(selector);
+  if (split.length === 1) split.unshift('');
+  res = [split[0]];
   for (o = 1; o < split.length; o++) {
-    res = cartesian(res, cartesian(parents, [split[o]]))
+    res = cartesian(res, cartesian(parents, [split[o]]));
   }
@@ -90,4 +93,4 @@ return res.join(',')
   return function iter(arg) {
-    if (type.call(arg) === ARRAY) for (var i= 0 ; i < arg.length; i ++) iter(arg[i])
-    else f(arg)
+    if (type.call(arg) === ARRAY) for (var i= 0 ; i < arg.length; i ++) iter(arg[i]);
+    else f(arg);
   }
@@ -113,3 +116,3 @@ }
 function declarations(state, emit, prefix, o, local) {
-  var k, v, kk
+  var k, v, kk;
   if (o==null) return
@@ -121,3 +124,3 @@
 
-      declarations(state, emit, prefix, o[k], local)
+      declarations(state, emit, prefix, o[k], local);
 
@@ -128,9 +131,9 @@ break
     // of the declarations list.
-    prefix = (prefix && prefix + '-')
+    prefix = (prefix && prefix + '-');
     for (k in o) if (own.call(o, k)){
-      v = o[k]
+      v = o[k];
       if (/\$/.test(k)) {
         for (kk in (k = k.split('$'))) if (own.call(k, kk)) {
 
-          declarations(state, emit, prefix + k[kk], v, local)
+          declarations(state, emit, prefix + k[kk], v, local);
 
@@ -140,3 +143,3 @@ }
 
-        declarations(state, emit, prefix + k, v, local)
+        declarations(state, emit, prefix + k, v, local);
 
@@ -155,3 +158,3 @@ }
     // restore the dashes
-    k = prefix.replace(/_/g, '-').replace(/[A-Z]/g, decamelize)
+    k = prefix.replace(/_/g, '-').replace(/[A-Z]/g, decamelize);
 
@@ -163,8 +166,8 @@ if (local && (k == 'animation-name' || k == 'animation' || k == 'list-style')) {
 
-        return o.replace(/(var\([^)]+\))|:?global\(\s*([_A-Za-z][-\w]*)\s*\)|()(-?[_A-Za-z][-\w]*)/, state.L)
+        return o.replace(/^\s*(?:(var\([^)]+\))|:?global\(\s*([_A-Za-z][-\w]*)\s*\)|()(-?[_A-Za-z][-\w]*))/, state.localizeReplacer)
 
-      }).join(',')
+      }).join(',');
     }
 
-    emit.d(k, o)
+    emit.decl(k, o);
 
@@ -175,3 +178,3 @@ }
 /**
- * Hanldes at-rules
+ * Handles a single at-rules
  *
@@ -183,4 +186,8 @@ * @param {object} state - holds the localizer- and walker-related methods
  *                    if takes both parameters and a block.
- * @param {string} prefix - the current selector or the selector prefix
- *                          in case of nested rules
+ *                    k == [match, fullAtRule, atRuleType, params?]
+ *                    So in `@-webkit-keyframes foo`, we have
+ *                     - match = "@-webkit-keyframes foo"
+ *                     - fullAtRule = "@-webkit-keyframes"
+ *                     - atRuleType = "keyframes"
+ *                     - params = "foo"
  * @param {string|string[]|object|object[]} v - Either parameters for
@@ -190,11 +197,14 @@ *                                              block-less rules or
  *                                              for the others.
- * @param {string} inAtRule - are we nested in an at-rule?
+ * @param {string} prefix - the current selector or the selector prefix
+ *                          in case of nested rules
  * @param {boolean} local - are we in @local or in @global scope?
+ * @param {string} nestingDepth - are we nested in an at-rule or a selector?
  */
 
-function atRules(state, emit, k, v, prefix, local, inAtRule) {
+function atRules(state, emit, k, v, prefix, local, nestingDepth) {
 
-  for (var i = 0; i < state.$a.length; i++) {
+  // First iterate over user-provided at-rules and return if one of them corresponds to the current one
+  for (var i = 0; i < state.$atHandlers.length; i++) {
 
-    if (state.$a[i](state, emit, k, v, prefix, local, inAtRule)) return
+    if (state.$atHandlers[i](state, emit, k, v, prefix, local, nestingDepth)) return
 
@@ -204,3 +214,3 @@ }
   // using `/^global$/.test(k[2])` rather that 'global' == k[2] gzips
-  // slightly better because of the regexps test further down.
+  // slightly better thanks to the regexps tests further down.
   // It is slightly less efficient but this isn't a critical path.
@@ -210,3 +220,3 @@
 
-    rules(state, emit, prefix, v, 0, inAtRule)
+    rules(state, emit, prefix, v, 0, nestingDepth);
 
@@ -216,3 +226,3 @@
 
-    rules(state, emit, prefix, v, 1, inAtRule)
+    rules(state, emit, prefix, v, 1, nestingDepth);
 
@@ -222,19 +232,19 @@
 
-    if (!local || inAtRule) return emit.a('@-error-bad-at-adopt-placement' , JSON.stringify(k[0]), 0)
+    if (!local || nestingDepth) return emit.err('@adopt global or nested: ' + k[0])
 
-    if (!/^\.?[_A-Za-z][-\w]*$/.test(k[3])) return emit.a('@-error-bad-at-adopter', k[3], 0)
+    if (!/^\.?[_A-Za-z][-\w]*$/.test(k[3])) return emit.err('bad adopter ' + JSON.stringify(k[3]) + ' in ' + k[0])
 
-    i = []
+    i = [];
     flatIter(function(adoptee, asString) {
 
-      if(!/^\.?[_A-Za-z][-\w]*(?:\s+\.?[_A-Za-z][-\w]*)*$/.test(asString = adoptee.toString())) emit.a('@-error-bad-at-adoptee', JSON.stringify(adoptee), 0)
+      if(adoptee == null || !/^\.?[_A-Za-z][-\w]*(?:\s+\.?[_A-Za-z][-\w]*)*$/.test(asString = adoptee + '')) emit.err('bad adoptee '+ JSON.stringify(adoptee) + ' in ' + k[0]);
 
-      else i.push(asString.replace(/\./g, ''))
+      else i.push(asString.replace(/\./g, ''));
 
-    })(v)
+    })(v);
 
     // we may end up with duplicate classes but AFAIK it has no consequences on specificity.
     if (i.length) {
-      state.l(k[3] = k[3].replace(/\./g, ''))
-      state.n[k[3]] += (' ' + i.join(' '))
+      state.localize(k[3] = k[3].replace(/\./g, ''));
+      state.names[k[3]] += (' ' + i.join(' '));
     }
@@ -246,5 +256,5 @@
 
-      emit.a(k[0], v)
+      emit.atrule(k[1], k[2], v);
 
-    })(v)
+    })(v);
 
@@ -255,9 +265,9 @@
 
-      emit.a(k[1], '', 1)
+      emit.atrule(k[1], k[2], k[3], 1);
 
-      declarations(state, emit, '', v, local)
+      declarations(state, emit, '', v, local);
 
-      emit.A(k[1], '')
+      emit._atrule();
 
-    })(v)
+    })(v);
 
@@ -270,12 +280,12 @@ } else if (k[3] && /^(?:media|supports|page|keyframes)$/.test(k[2])) {
         /(var\([^)]+\))|:?global\(\s*([_A-Za-z][-\w]*)\s*\)|()(-?[_A-Za-z][-\w]*)/,
-        state.L
-      )
+        state.localizeReplacer
+      );
     }
 
 
-    emit.a(k[1], k[3], 1)
+    emit.atrule(k[1], k[2], k[3], 1);
 
     if ('page' == k[2]) {
 
-      declarations(state, emit, '', v, local)
+      declarations(state, emit, '', v, local);
 
@@ -287,12 +297,12 @@ } else {
         'keyframes' == k[2] ? '' : prefix,
-        v, local, 1
-      )
+        v, local, nestingDepth + 1
+      );
 
     }
 
-    emit.A(k[1], k[3])
+    emit._atrule();
 
   } else {
 
-    emit.a('@-error-unsupported-at-rule', JSON.stringify(k[0]))
+    emit.err('Unsupported at-rule: ' + k[0]);
 
@@ -310,7 +320,7 @@ }
  * @param {array|string|object} tree - a source object or sub-object.
- * @param {string} inAtRule - are we nested in an at-rule?
+ * @param {string} nestingDepth - are we nested in an at-rule?
  * @param {boolean} local - are we in @local or in @global scope?
  */
-function rules(state, emit, prefix, tree, local, inAtRule) {
-  var k, v, inDeclaration, kk
+function rules(state, emit, prefix, tree, local, nestingDepth) {
+  var k, v, inDeclaration, kk;
 
@@ -321,9 +331,9 @@ switch (type.call(tree)) {
     for (k in tree) if (own.call(tree, k)) {
-      v = tree[k]
+      v = tree[k];
 
       if (prefix.length > 0 && /^[-\w$]+$/.test(k)) {
         if (!inDeclaration) {
-          inDeclaration = 1
+          inDeclaration = 1;
 
-          emit.s(prefix)
+          emit.rule(prefix);
 
@@ -334,3 +344,3 @@ }
 
-            declarations(state, emit, k[kk], v, local)
+            declarations(state, emit, k[kk], v, local);
 
@@ -340,3 +350,3 @@ }
 
-          declarations(state, emit, k, v, local)
+          declarations(state, emit, k, v, local);
 
@@ -347,20 +357,20 @@ }
         // Handle At-rules
-        inDeclaration = 0
+        inDeclaration = 0;
 
         atRules(state, emit,
           /^(.(?:-[\w]+-)?([_A-Za-z][-\w]*))\b\s*(.*?)\s*$/.exec(k) || [k,'@','',''],
-          v, prefix, local, inAtRule
-        )
+          v, prefix, local, nestingDepth
+        );
 
       } else {
         // selector or nested sub-selectors
-        inDeclaration = 0
+        inDeclaration = 0;
 
         rules(
           state, emit,
-          // `prefix` ... Hefty. Ugly. Sadly necessary.
-          //
-          (prefix.length > 0 && (/,/.test(prefix) || /,/.test(k))) ?
+          // build the selector `prefix` for the next iteration.
+          // ugly and full of redundant bits but so far the fastest/shortest.gz
+          /*0 if*/(prefix.length > 0 && (/,/.test(prefix) || /,/.test(k))) ?
 
-            /*0*/ (kk = splitSelector(prefix), splitSelector(
+            /*0 then*/ (kk = splitSelector(prefix), splitSelector(
               local ?
@@ -370,3 +380,3 @@
                   /("(?:\\.|[^"\n])*"|'(?:\\.|[^'\n])*'|\/\*[\s\S]*?\*\/)|:global\(\s*(\.-?[_A-Za-z][-\w]*)\s*\)|(\.)(-?[_A-Za-z][-\w]*)/g,
-                  state.L
+                  state.localizeReplacer
                 ) :
@@ -381,5 +391,5 @@
 
-            /*0*/ /&/.test(k) ?
+            /*0 else*/ /*1 if*/ /&/.test(k) ?
 
-              /*1*/ ampersand(
+              /*1 then*/ ampersand(
                 local ?
@@ -389,3 +399,3 @@
                     /("(?:\\.|[^"\n])*"|'(?:\\.|[^'\n])*'|\/\*[\s\S]*?\*\/)|:global\(\s*(\.-?[_A-Za-z][-\w]*)\s*\)|(\.)(-?[_A-Za-z][-\w]*)/g,
-                    state.L
+                    state.localizeReplacer
                   ) :
@@ -397,3 +407,3 @@
 
-              /*1*/ prefix + (
+              /*1 else*/ prefix + (
                 local ?
@@ -403,3 +413,3 @@
                     /("(?:\\.|[^"\n])*"|'(?:\\.|[^'\n])*'|\/\*[\s\S]*?\*\/)|:global\(\s*(\.-?[_A-Za-z][-\w]*)\s*\)|(\.)(-?[_A-Za-z][-\w]*)/g,
-                    state.L
+                    state.localizeReplacer
                   ) :
@@ -409,4 +419,4 @@
                 ),
-           v, local, inAtRule
-        )
+           v, local, nestingDepth + 1
+        );
 
@@ -421,3 +431,3 @@ }
 
-      rules(state, emit, prefix, tree[k], local, inAtRule)
+      rules(state, emit, prefix, tree[k], local, nestingDepth);
 
@@ -429,7 +439,7 @@ }
     // CSS hacks or ouptut of `j2c.inline`.
+    if (!prefix.length) emit.err('No selector');
+    emit.rule(prefix || ' ');
 
-    emit.s(prefix.length > 0 ? prefix : ':-error-no-selector')
+    declarations(state, emit, '', tree, local);
 
-    declarations(state, emit, '', tree, local)
-
   }
@@ -445,28 +455,27 @@ }
 // contains arrays.
-// There's no `S` handler, because the core compiler never
+// There's no `_rule` handler, because the core compiler never
 // calls it.
 function closeSelectors(next, inline) {
-  var lastSelector
+  var lastSelector;
   return inline ? next : {
-    i: function(){lastSelector = 0; next.i()},
-    x: function (raw) {
-      if (lastSelector) {next.S(); lastSelector = 0}
-      return next.x(raw)
+    init: function(){lastSelector = 0; next.init();},
+    done: function (raw) {
+      if (lastSelector) {next._rule(); lastSelector = 0;}
+      return next.done(raw)
     },
-    a: function (rule, param, takesBlock) {
-      if (lastSelector) {next.S(); lastSelector = 0}
-      next.a(rule, param, takesBlock)
+    atrule: function (rule, kind, param, takesBlock) {
+      if (lastSelector) {next._rule(); lastSelector = 0;}
+      next.atrule(rule, kind, param, takesBlock);
     },
-    A: function (rule) {
-      if (lastSelector) {next.S(); lastSelector = 0}
-      next.A(rule)
+    _atrule: function (rule) {
+      if (lastSelector) {next._rule(); lastSelector = 0;}
+      next._atrule(rule);
     },
-    s: function (selector) {
+    rule: function (selector) {
       if (selector !== lastSelector){
-        if (lastSelector) next.S()
-        next.s(selector)
-        lastSelector = selector
+        if (lastSelector) next._rule();
+        next.rule(selector);
+        lastSelector = selector;
       }
-    },
-    d: next.d
+    }
   }
@@ -480,4 +489,4 @@ }
 function kv (k, v, o) {
-  o = {}
-  o[k] = v
+  o = {};
+  o[k] = v;
   return o
@@ -491,5 +500,5 @@ }
     // inner curry!
-    var _at = at.bind.apply(at, [null].concat([].slice.call(arguments,0)))
+    var _at = at.bind.apply(at, [null].concat([].slice.call(arguments,0)));
     // So that it can be used as a key in an ES6 object literal.
-    _at.toString = function(){return '@' + rule + ' ' + params}
+    _at.toString = function(){return '@' + rule + ' ' + params};
     return _at
@@ -502,28 +511,32 @@ }
 
-  // palceholder for the buffer used by the `$sink` handlers
-  var buf
+  // the buffer that accumulates the output. Initialized in `$sink.i()`
+  var buf, err;
 
   // the bottom of the 'codegen' stream. Mirrors the `$filter` plugin API.
   var $sink = {
-    // Init
-    i: function(){buf=[]},
-    // done (eXit)
-    x: function (raw) {return raw ? buf : buf.join('')},
-    // start At-rule
-    a: function (rule, argument, takesBlock) {
-      buf.push(rule, argument && ' ',argument, takesBlock ? ' {\n' : ';\n')
+    init: function(){buf=[], err=[];},
+    done: function (raw) {
+      if (err.length != 0) throw new Error('j2c error(s): ' + JSON.stringify(err,null,2) + 'in context:\n' + buf.join(''))
+      return raw ? buf : buf.join('')
     },
-    // end At-rule
-    A: function ()            {buf.push('}\n')},
-    // start Selector
-    s: function (selector)    {buf.push(selector, ' {\n')},
-    // end Selector
-    S: function ()            {buf.push('}\n')},
-    // declarations
-    d: function (prop, value) {buf.push(prop, prop && ':', value, ';\n')}
-  }
+    err: function(msg) {
+      err.push(msg);
+      buf.push('/* +++ ERROR +++ ' + msg + ' */\n');
+    },
+    atrule: function (rule, kind, param, takesBlock) {
+      buf.push(rule, param && ' ', param, takesBlock ? ' {' : ';', _instance.endline);
+    },
+    // close atrule
+    _atrule: function () {buf.push('}', _instance.endline);},
+    rule: function (selector) {buf.push(selector, ' {', _instance.endline);},
+    // close rule
+    _rule: function () {buf.push('}', _instance.endline);},
+    decl: function (prop, value) {buf.push(prop, prop && ':', value, ';', _instance.endline);}
+  };
 
-  var $filters = [closeSelectors]
-  var $atHandlers = []
+  // holds the `$filter` and `$at` handlers
+  var $filters = [closeSelectors];
+  var $atHandlers = [];
 
+  // the public API (see the main docs)
   var _instance = {
@@ -534,3 +547,5 @@ at: at,
     names: {},
+    endline: '\n',
     suffix: '__j2c-' +
+      // 128 bits of randomness
       Math.floor(Math.random() * 0x100000000).toString(36) + '-' +
@@ -540,13 +555,32 @@ Math.floor(Math.random() * 0x100000000).toString(36) + '-' +
       Math.floor(Math.random() * 0x100000000).toString(36),
-    use: function() {
-      _use(emptyArray.slice.call(arguments))
-      return _instance
+    $plugins: [],
+    sheet: function(tree) {
+      var emit = _createOrRetrieveStream(0);
+      emit.init();
+      rules(
+        _walkers[0],
+        emit,
+        '', // prefix
+        tree,
+        1,  // local, by default
+        0   // nesting depth
+      );
+
+      return emit.done()
     },
-    $plugins: []
-  }
+    inline: function (tree, options) {
+      var emit = _createOrRetrieveStream(1);
+      emit.init();
+      declarations(
+        _walkers[1],
+        emit,
+        '', // prefix
+        tree,
+        !(options && options.global)   // local, by default
+      );
+      return emit.done()
+    }
+  };
 
-  var _streams = []
-
-  // The `state` (for the core) / `walker` (for the plugins) tables.
-
+  // The `state` (for the core functions) / `walker` (for the plugins) tables.
   var _walkers = [
@@ -556,51 +590,21 @@ // for j2c.sheet
       // helpers for locaizing class and animation names
-      L: _localizeReplacer, // second argument to String.prototype.replace
-      l: _localize,         // mangles local names
-      n: _instance.names,    // local => mangled mapping
-      $a: $atHandlers,      // extra at-rules
+      localizeReplacer: _localizeReplacer, // second argument to String.prototype.replace
+      localize: _localize,                 // mangles local names
+      names: _instance.names,              // local => mangled mapping
+      $atHandlers: $atHandlers,            // extra at-rules
       // The core walker methods, to be provided to plugins
-      a: atRules,
-      d: declarations,
-      r: rules
+      atrule: atRules,
+      decl: declarations,
+      rule: rules
     },
     // likewise, for j2c.inline (idem with `$a`, `a` and `s` removed)
     {
-      L: _localizeReplacer,
-      l: _localize,
-      n: _instance.names,
-      d: declarations
+      localizeReplacer: _localizeReplacer,
+      localize: _localize,
+      names: _instance.names,
+      decl: declarations
     }
-  ]
+  ];
 
 
-  // The main API functions
-
-  _instance.sheet = function(tree) {
-    var emit = _getStream(0)
-    emit.i()
-    rules(
-      _walkers[0],
-      emit,
-      '',    // prefix
-      tree,
-      1,      // local, by default
-      0     // inAtRule
-    )
-
-    return emit.x()
-  }
-
-  _instance.inline = function (tree) {
-    var emit = _getStream(1)
-    emit.i()
-    declarations(
-      _walkers[1],
-      emit,
-      '',         // prefix
-      tree,
-      1           //local
-    )
-    return emit.x()
-  }
-
   // inner helpers
@@ -615,5 +619,5 @@
 
-    _instance.$plugins.push(plugin)
+    _instance.$plugins.push(plugin);
 
-    if (type.call(plugin) === FUNCTION) plugin = plugin(_instance)
+    if (type.call(plugin) === FUNCTION) plugin = plugin(_instance);
 
@@ -623,50 +627,74 @@ if (!plugin) return
     flatIter(function(filter) {
-      $filters.push(filter)
-    })(plugin.$filter || emptyArray)
+      $filters.push(filter);
+    })(plugin.$filter || emptyArray);
 
     flatIter(function(handler) {
-      $atHandlers.push(handler)
-    })(plugin.$at || emptyArray)
+      $atHandlers.push(handler);
+    })(plugin.$at || emptyArray);
 
-    Default(_instance.names, plugin.$names || emptyObject)
+    defaults(_instance.names, plugin.$names || emptyObject);
 
-    _use(plugin.$plugins || emptyArray)
+    _use(plugin.$plugins || emptyArray);
 
-    $sink = plugin.$sink || $sink
+    $sink = plugin.$sink || $sink;
 
-    Default(_instance, plugin)
-  })
+    defaults(_instance, plugin);
+  });
 
-  function _getStream(inline) {
+
+  var _streams = [];
+  /**
+   * returns the codegen streams, creating them if necessary
+   * @param
+   */
+  function _createOrRetrieveStream(inline) {
+    // build the stream processors if needed
     if (!_streams.length) {
-      for(var i = 0; i < 2; i++){
-        $filters[$filters.length - i] = function(_, inline) {return inline ? {i:$sink.i, d:$sink.d, x:$sink.x} : $sink}
+      // append the $sink as the ultimate filter
+      $filters.push(function(_, inline) {return inline ? {init:$sink.init, decl:$sink.decl, done:$sink.done, err: $sink.err} : $sink});
+      for(var i = 0; i < 2; i++){ // 0 for j2c.sheet, 1 for j2c.inline
         for (var j = $filters.length; j--;) {
-          _streams[i] = freeze(Default(
-            $filters[j](_streams[i], !!i, _walkers[i]),
-            _streams[i]
-          ))
+          _streams[i] = freeze(
+            defaults(
+              $filters[j](_streams[i], !!i),
+              _streams[i]
+            )
+          );
         }
       }
     }
-    var res = _streams[inline]
-    return res
+    return _streams[inline]
   }
 
+  /**
+   * Returns a localized version of a given name.
+   * Registers the pair in `instnace.name` if needed.
+   *
+   * @param {string} name - the name to localize
+   * @return {string} - the localized version
+   */
   function _localize(name) {
-    if (!_instance.names[name]) _instance.names[name] = name + _instance.suffix
+    if (!_instance.names[name]) _instance.names[name] = name + _instance.suffix;
     return _instance.names[name].match(/^\S+/)
   }
 
-  function _localizeReplacer(match, string, global, dot, name) {
-    if (string || global) return string || global
-    return dot + _localize(name)
+  /**
+   * Used as second argument for str.replace(localizeRegex, replacer)
+   * `ignore`, `global` and `(dot, name)` are mutually exclusive
+   *
+   * @param {string} match - the whole match (ignored)
+   * @param {string|null} ignore - a comment or a string literal
+   * @param {string|null} global - a global name
+   * @param {string|null} dot - either '.' for a local class name or the empty string otherwise
+   * @param {string|null} name - the name to localize
+   * @return {string}
+   */
+  function _localizeReplacer(match, ignore, global$$1, dot, name) {
+    return ignore || global$$1 || dot + _localize(name)
   }
 
+  _use(emptyArray.slice.call(arguments));
   return _instance
 }
 
-var _j2c = j2c()
-'sheet|inline|names|at|global|kv|suffix'.split('|').map(function(m){j2c[m] = _j2c[m]})
-
-export default j2c;
+export default j2c;

dist/j2c.global.js

 var j2c = (function () {
-  'use strict';
+'use strict';
 
-  var emptyArray = [];
-  var emptyObject = {};
-  var type = emptyObject.toString;
-  var ARRAY =  type.call(emptyArray);
-  var OBJECT = type.call(emptyObject);
-  var STRING = type.call('');
-  var FUNCTION = type.call(type);
-  var own =  emptyObject.hasOwnProperty;
-  var freeze = Object.freeze || function(o) {return o};
-  function Default(target, source) {
-    for (var k in source) if (own.call(source, k)) {
-      if (k.indexOf('$') && !(k in target)) target[k] = source[k]
-    }
-    return target
-  }
+var emptyArray = [];
+var emptyObject = {};
+var type = emptyObject.toString;
+var ARRAY =  type.call(emptyArray);
+var OBJECT = type.call(emptyObject);
+var STRING = type.call('');
+var FUNCTION = type.call(type);
+var own =  emptyObject.hasOwnProperty;
+var freeze = Object.freeze || function(o) {return o};
 
-  function cartesian(a,b) {
-    var res = [], i, j
-    for (j in b) if(own.call(b, j))
-      for (i in a) if(own.call(a, i))
-        res.push(a[i] + b[j])
-    return res
+
+function defaults(target, source) {
+  for (var k in source) if (own.call(source, k)) {
+    if (k.indexOf('$') && !(k in target)) target[k] = source[k];
   }
+  return target
+}
 
-  // "Tokenizes" the selectors into parts relevant for the next function.
-  // Strings and comments are matched, but ignored afterwards.
-  // This is not a full tokenizers. It only recognizes comas, parentheses,
-  // strings and comments.
-  // regexp generated by scripts/regexps.js then trimmed by hand
-  var selectorTokenizer = /[(),]|"(?:\\.|[^"\n])*"|'(?:\\.|[^'\n])*'|\/\*[\s\S]*?\*\//g
+function cartesian(a,b) {
+  var res = [], i, j;
+  for (j in b) if(own.call(b, j))
+    for (i in a) if(own.call(a, i))
+      res.push(a[i] + b[j]);
+  return res
+}
 
+// "Tokenizes" the selectors into parts relevant for the next function.
+// Strings and comments are matched, but ignored afterwards.
+// This is not a full tokenizers. It only recognizes comas, parentheses,
+// strings and comments.
+// regexp generated by scripts/regexps.js then trimmed by hand
+var selectorTokenizer = /[(),]|"(?:\\.|[^"\n])*"|'(?:\\.|[^'\n])*'|\/\*[\s\S]*?\*\//g;
 
-  /**
-   * This will split a coma-separated selector list into individual selectors,
-   * ignoring comas in strings, comments and in :pseudo-selectors(parameter, lists).
-   * @param {string} selector
-   * @return {string[]}
-   */
 
-  function splitSelector(selector) {
-    var indices = [], res = [], inParen = 0, o
-    /*eslint-disable no-cond-assign*/
-    while (o = selectorTokenizer.exec(selector)) {
-    /*eslint-enable no-cond-assign*/
-      switch (o[0]) {
-      case '(': inParen++; break
-      case ')': inParen--; break
-      case ',': if (inParen) break; indices.push(o.index)
-      }
+/**
+ * This will split a coma-separated selector list into individual selectors,
+ * ignoring comas in strings, comments and in :pseudo-selectors(parameter, lists).
+ *
+ * @param {string} selector
+ * @return {string[]}
+ */
+
+function splitSelector(selector) {
+  var indices = [], res = [], inParen = 0, o;
+  /*eslint-disable no-cond-assign*/
+  while (o = selectorTokenizer.exec(selector)) {
+  /*eslint-enable no-cond-assign*/
+    switch (o[0]) {
+    case '(': inParen++; break
+    case ')': inParen--; break
+    case ',': if (inParen) break; indices.push(o.index);
     }
-    for (o = indices.length; o--;){
-      res.unshift(selector.slice(indices[o] + 1))
-      selector = selector.slice(0, indices[o])
-    }
-    res.unshift(selector)
-    return res
   }
+  for (o = indices.length; o--;){
+    res.unshift(selector.slice(indices[o] + 1));
+    selector = selector.slice(0, indices[o]);
+  }
+  res.unshift(selector);
+  return res
+}
 
-  // This is like the `selectorTokenizer`, but for the `&` operator
+// Like the `selectorTokenizer`, but for the `&` operator
+var ampersandTokenizer = /&|"(?:\\.|[^"\n])*"|'(?:\\.|[^'\n])*'|\/\*[\s\S]*?\*\//g;
 
-  var ampersandTokenizer = /&|"(?:\\.|[^"\n])*"|'(?:\\.|[^'\n])*'|\/\*[\s\S]*?\*\//g
-
-  function ampersand (selector, parents) {
-    var indices = [], split = [], res, o
-    /*eslint-disable no-cond-assign*/
-    while (o = ampersandTokenizer.exec(selector)) {
-    /*eslint-enable no-cond-assign*/
-      if (o[0] == '&') indices.push(o.index)
-    }
-    for (o = indices.length; o--;){
-      split.unshift(selector.slice(indices[o] + 1))
-      selector = selector.slice(0, indices[o])
-    }
-    split.unshift(selector)
-    res = [split[0]]
-    for (o = 1; o < split.length; o++) {
-      res = cartesian(res, cartesian(parents, [split[o]]))
-    }
-    return res.join(',')
+function ampersand (selector, parents) {
+  var indices = [], split = [], res, o;
+  /*eslint-disable no-cond-assign*/
+  while (o = ampersandTokenizer.exec(selector)) {
+  /*eslint-enable no-cond-assign*/
+    if (o[0] == '&') indices.push(o.index);
   }
-
-  function flatIter (f) {
-    return function iter(arg) {
-      if (type.call(arg) === ARRAY) for (var i= 0 ; i < arg.length; i ++) iter(arg[i])
-      else f(arg)
-    }
+  for (o = indices.length; o--;){
+    split.unshift(selector.slice(indices[o] + 1));
+    selector = selector.slice(0, indices[o]);
   }
+  split.unshift(selector);
+  if (split.length === 1) split.unshift('');
+  res = [split[0]];
+  for (o = 1; o < split.length; o++) {
+    res = cartesian(res, cartesian(parents, [split[o]]));
+  }
+  return res.join(',')
+}
 
-  function decamelize(match) {
-    return '-' + match.toLowerCase()
+function flatIter (f) {
+  return function iter(arg) {
+    if (type.call(arg) === ARRAY) for (var i= 0 ; i < arg.length; i ++) iter(arg[i]);
+    else f(arg);
   }
+}
 
-  /**
-   * Handles the property:value; pairs.
-   *
-   * @param {object} state - holds the localizer- and walker-related methods
-   *                         and state
-   * @param {object} emit - the contextual emitters to the final buffer
-   * @param {string} prefix - the current property or a prefix in case of nested
-   *                          sub-properties.
-   * @param {array|object|string} o - the declarations.
-   * @param {boolean} local - are we in @local or in @global scope.
-   */
+function decamelize(match) {
+  return '-' + match.toLowerCase()
+}
 
-  function declarations(state, emit, prefix, o, local) {
-    var k, v, kk
-    if (o==null) return
+/**
+ * Handles the property:value; pairs.
+ *
+ * @param {object} state - holds the localizer- and walker-related methods
+ *                         and state
+ * @param {object} emit - the contextual emitters to the final buffer
+ * @param {string} prefix - the current property or a prefix in case of nested
+ *                          sub-properties.
+ * @param {array|object|string} o - the declarations.
+ * @param {boolean} local - are we in @local or in @global scope.
+ */
 
-    switch ( type.call(o = o.valueOf()) ) {
-    case ARRAY:
-      for (k = 0; k < o.length; k++)
+function declarations(state, emit, prefix, o, local) {
+  var k, v, kk;
+  if (o==null) return
 
-        declarations(state, emit, prefix, o[k], local)
+  switch ( type.call(o = o.valueOf()) ) {
+  case ARRAY:
+    for (k = 0; k < o.length; k++)
 
-      break
-    case OBJECT:
-      // prefix is falsy iif it is the empty string, which means we're at the root
-      // of the declarations list.
-      prefix = (prefix && prefix + '-')
-      for (k in o) if (own.call(o, k)){
-        v = o[k]
-        if (/\$/.test(k)) {
-          for (kk in (k = k.split('$'))) if (own.call(k, kk)) {
+      declarations(state, emit, prefix, o[k], local);
 
-            declarations(state, emit, prefix + k[kk], v, local)
+    break
+  case OBJECT:
+    // prefix is falsy iif it is the empty string, which means we're at the root
+    // of the declarations list.
+    prefix = (prefix && prefix + '-');
+    for (k in o) if (own.call(o, k)){
+      v = o[k];
+      if (/\$/.test(k)) {
+        for (kk in (k = k.split('$'))) if (own.call(k, kk)) {
 
-          }
-        } else {
+          declarations(state, emit, prefix + k[kk], v, local);
 
-          declarations(state, emit, prefix + k, v, local)
-
         }
-      }
-      break
-    default:
-      // prefix is falsy when it is "", which means that we're
-      // at the top level.
-      // `o` is then treated as a `property:value` pair, or a
-      // semi-colon-separated list thereof.
-      // Otherwise, `prefix` is the property name, and
-      // `o` is the value.
+      } else {
 
-      // restore the dashes
-      k = prefix.replace(/_/g, '-').replace(/[A-Z]/g, decamelize)
+        declarations(state, emit, prefix + k, v, local);
 
-      if (local && (k == 'animation-name' || k == 'animation' || k == 'list-style')) {
-        // no need to tokenize here a plain `.split(',')` has all bases covered.
-        // We may 'localize' a comment, but it's not a big deal.
-        o = o.split(',').map(function (o) {
+      }
+    }
+    break
+  default:
+    // prefix is falsy when it is "", which means that we're
+    // at the top level.
+    // `o` is then treated as a `property:value` pair, or a
+    // semi-colon-separated list thereof.
+    // Otherwise, `prefix` is the property name, and
+    // `o` is the value.
 
-          return o.replace(/(var\([^)]+\))|:?global\(\s*([_A-Za-z][-\w]*)\s*\)|()(-?[_A-Za-z][-\w]*)/, state.L)
+    // restore the dashes
+    k = prefix.replace(/_/g, '-').replace(/[A-Z]/g, decamelize);
 
-        }).join(',')
-      }
+    if (local && (k == 'animation-name' || k == 'animation' || k == 'list-style')) {
+      // no need to tokenize here a plain `.split(',')` has all bases covered.
+      // We may 'localize' a comment, but it's not a big deal.
+      o = o.split(',').map(function (o) {
 
-      emit.d(k, o)
+        return o.replace(/^\s*(?:(var\([^)]+\))|:?global\(\s*([_A-Za-z][-\w]*)\s*\)|()(-?[_A-Za-z][-\w]*))/, state.localizeReplacer)
 
+      }).join(',');
     }
-  }
 
-  /**
-   * Hanldes at-rules
-   *
-   * @param {object} state - holds the localizer- and walker-related methods
-   *                         and state
-   * @param {object} emit - the contextual emitters to the final buffer
-   * @param {array} k - The parsed at-rule, including the parameters,
-   *                    if takes both parameters and a block.
-   * @param {string} prefix - the current selector or the selector prefix
-   *                          in case of nested rules
-   * @param {string|string[]|object|object[]} v - Either parameters for
-   *                                              block-less rules or
-   *                                              their block
-   *                                              for the others.
-   * @param {string} inAtRule - are we nested in an at-rule?
-   * @param {boolean} local - are we in @local or in @global scope?
-   */
+    emit.decl(k, o);
 
-  function atRules(state, emit, k, v, prefix, local, inAtRule) {
+  }
+}
 
-    for (var i = 0; i < state.$a.length; i++) {
+/**
+ * Handles a single at-rules
+ *
+ * @param {object} state - holds the localizer- and walker-related methods
+ *                         and state
+ * @param {object} emit - the contextual emitters to the final buffer
+ * @param {array} k - The parsed at-rule, including the parameters,
+ *                    if takes both parameters and a block.
+ *                    k == [match, fullAtRule, atRuleType, params?]
+ *                    So in `@-webkit-keyframes foo`, we have
+ *                     - match = "@-webkit-keyframes foo"
+ *                     - fullAtRule = "@-webkit-keyframes"
+ *                     - atRuleType = "keyframes"
+ *                     - params = "foo"
+ * @param {string|string[]|object|object[]} v - Either parameters for
+ *                                              block-less rules or
+ *                                              their block
+ *                                              for the others.
+ * @param {string} prefix - the current selector or the selector prefix
+ *                          in case of nested rules
+ * @param {boolean} local - are we in @local or in @global scope?
+ * @param {string} nestingDepth - are we nested in an at-rule or a selector?
+ */
 
-      if (state.$a[i](state, emit, k, v, prefix, local, inAtRule)) return
+function atRules(state, emit, k, v, prefix, local, nestingDepth) {
 
-    }
+  // First iterate over user-provided at-rules and return if one of them corresponds to the current one
+  for (var i = 0; i < state.$atHandlers.length; i++) {
 
-    // using `/^global$/.test(k[2])` rather that 'global' == k[2] gzips
-    // slightly better because of the regexps test further down.
-    // It is slightly less efficient but this isn't a critical path.
+    if (state.$atHandlers[i](state, emit, k, v, prefix, local, nestingDepth)) return
 
-    if (!k[3] && /^global$/.test(k[2])) {
+  }
 
-      rules(state, emit, prefix, v, 0, inAtRule)
+  // using `/^global$/.test(k[2])` rather that 'global' == k[2] gzips
+  // slightly better thanks to the regexps tests further down.
+  // It is slightly less efficient but this isn't a critical path.
 
+  if (!k[3] && /^global$/.test(k[2])) {
 
-    } else if (!k[3] && /^local$/.test(k[2])) {
+    rules(state, emit, prefix, v, 0, nestingDepth);
 
-      rules(state, emit, prefix, v, 1, inAtRule)
 
+  } else if (!k[3] && /^local$/.test(k[2])) {
 
-    } else if (k[3] && /^adopt$/.test(k[2])) {
+    rules(state, emit, prefix, v, 1, nestingDepth);
 
-      if (!local || inAtRule) return emit.a('@-error-bad-at-adopt-placement' , JSON.stringify(k[0]), 0)
 
-      if (!/^\.?[_A-Za-z][-\w]*$/.test(k[3])) return emit.a('@-error-bad-at-adopter', k[3], 0)
+  } else if (k[3] && /^adopt$/.test(k[2])) {
 
-      i = []
-      flatIter(function(adoptee, asString) {
+    if (!local || nestingDepth) return emit.err('@adopt global or nested: ' + k[0])
 
-        if(!/^\.?[_A-Za-z][-\w]*(?:\s+\.?[_A-Za-z][-\w]*)*$/.test(asString = adoptee.toString())) emit.a('@-error-bad-at-adoptee', JSON.stringify(adoptee), 0)
+    if (!/^\.?[_A-Za-z][-\w]*$/.test(k[3])) return emit.err('bad adopter ' + JSON.stringify(k[3]) + ' in ' + k[0])
 
-        else i.push(asString.replace(/\./g, ''))
+    i = [];
+    flatIter(function(adoptee, asString) {
 
-      })(v)
+      if(adoptee == null || !/^\.?[_A-Za-z][-\w]*(?:\s+\.?[_A-Za-z][-\w]*)*$/.test(asString = adoptee + '')) emit.err('bad adoptee '+ JSON.stringify(adoptee) + ' in ' + k[0]);
 
-      // we may end up with duplicate classes but AFAIK it has no consequences on specificity.
-      if (i.length) {
-        state.l(k[3] = k[3].replace(/\./g, ''))
-        state.n[k[3]] += (' ' + i.join(' '))
-      }
+      else i.push(asString.replace(/\./g, ''));
 
+    })(v);
 
-    } else if (!k[3] && /^(?:namespace|import|charset)$/.test(k[2])) {
-      flatIter(function(v) {
+    // we may end up with duplicate classes but AFAIK it has no consequences on specificity.
+    if (i.length) {
+      state.localize(k[3] = k[3].replace(/\./g, ''));
+      state.names[k[3]] += (' ' + i.join(' '));
+    }
 
-        emit.a(k[0], v)
 
-      })(v)
+  } else if (!k[3] && /^(?:namespace|import|charset)$/.test(k[2])) {
+    flatIter(function(v) {
 
+      emit.atrule(k[1], k[2], v);
 
-    } else if (!k[3] && /^(?:font-face|viewport)$/.test(k[2])) {
-      flatIter(function(v) {
+    })(v);
 
-        emit.a(k[1], '', 1)
 
-        declarations(state, emit, '', v, local)
+  } else if (!k[3] && /^(?:font-face|viewport)$/.test(k[2])) {
+    flatIter(function(v) {
 
-        emit.A(k[1], '')
+      emit.atrule(k[1], k[2], k[3], 1);
 
-      })(v)
+      declarations(state, emit, '', v, local);
 
-    } else if (k[3] && /^(?:media|supports|page|keyframes)$/.test(k[2])) {
+      emit._atrule();
 
-      if (local && 'keyframes' == k[2]) {
-        k[3] = k[3].replace(
-          // generated by script/regexps.js
-          /(var\([^)]+\))|:?global\(\s*([_A-Za-z][-\w]*)\s*\)|()(-?[_A-Za-z][-\w]*)/,
-          state.L
-        )
-      }
+    })(v);
 
+  } else if (k[3] && /^(?:media|supports|page|keyframes)$/.test(k[2])) {
 
-      emit.a(k[1], k[3], 1)
+    if (local && 'keyframes' == k[2]) {
+      k[3] = k[3].replace(
+        // generated by script/regexps.js
+        /(var\([^)]+\))|:?global\(\s*([_A-Za-z][-\w]*)\s*\)|()(-?[_A-Za-z][-\w]*)/,
+        state.localizeReplacer
+      );
+    }
 
-      if ('page' == k[2]) {
 
-        declarations(state, emit, '', v, local)
+    emit.atrule(k[1], k[2], k[3], 1);
 
-      } else {
+    if ('page' == k[2]) {
 
-        rules(
-          state, emit,
-          'keyframes' == k[2] ? '' : prefix,
-          v, local, 1
-        )
+      declarations(state, emit, '', v, local);
 
-      }
-
-      emit.A(k[1], k[3])
-
     } else {
 
-      emit.a('@-error-unsupported-at-rule', JSON.stringify(k[0]))
+      rules(
+        state, emit,
+        'keyframes' == k[2] ? '' : prefix,
+        v, local, nestingDepth + 1
+      );
 
     }
-  }
 
-  /**
-   * Add rulesets and other CSS tree to the sheet.
-   *
-   * @param {object} state - holds the localizer- and walker-related methods
-   *                         and state
-   * @param {object} emit - the contextual emitters to the final buffer
-   * @param {string} prefix - the current selector or a prefix in case of nested rules
-   * @param {array|string|object} tree - a source object or sub-object.
-   * @param {string} inAtRule - are we nested in an at-rule?
-   * @param {boolean} local - are we in @local or in @global scope?
-   */
-  function rules(state, emit, prefix, tree, local, inAtRule) {
-    var k, v, inDeclaration, kk
+    emit._atrule();
 
-    switch (type.call(tree)) {
+  } else {
 
-    case OBJECT:
-      for (k in tree) if (own.call(tree, k)) {
-        v = tree[k]
+    emit.err('Unsupported at-rule: ' + k[0]);
 
-        if (prefix.length > 0 && /^[-\w$]+$/.test(k)) {
-          if (!inDeclaration) {
-            inDeclaration = 1
+  }
+}
 
-            emit.s(prefix)
+/**
+ * Add rulesets and other CSS tree to the sheet.
+ *
+ * @param {object} state - holds the localizer- and walker-related methods
+ *                         and state
+ * @param {object} emit - the contextual emitters to the final buffer
+ * @param {string} prefix - the current selector or a prefix in case of nested rules
+ * @param {array|string|object} tree - a source object or sub-object.
+ * @param {string} nestingDepth - are we nested in an at-rule?
+ * @param {boolean} local - are we in @local or in @global scope?
+ */
+function rules(state, emit, prefix, tree, local, nestingDepth) {
+  var k, v, inDeclaration, kk;
 
-          }
-          if (/\$/.test(k)) {
-            for (kk in (k = k.split('$'))) if (own.call(k, kk)) {
+  switch (type.call(tree)) {
 
-              declarations(state, emit, k[kk], v, local)
+  case OBJECT:
+    for (k in tree) if (own.call(tree, k)) {
+      v = tree[k];
 
-            }
-          } else {
+      if (prefix.length > 0 && /^[-\w$]+$/.test(k)) {
+        if (!inDeclaration) {
+          inDeclaration = 1;
 
-            declarations(state, emit, k, v, local)
+          emit.rule(prefix);
 
-          }
+        }
+        if (/\$/.test(k)) {
+          for (kk in (k = k.split('$'))) if (own.call(k, kk)) {
 
-        } else if (/^@/.test(k)) {
-          // Handle At-rules
-          inDeclaration = 0
+            declarations(state, emit, k[kk], v, local);
 
-          atRules(state, emit,
-            /^(.(?:-[\w]+-)?([_A-Za-z][-\w]*))\b\s*(.*?)\s*$/.exec(k) || [k,'@','',''],
-            v, prefix, local, inAtRule
-          )
-
+          }
         } else {
-          // selector or nested sub-selectors
-          inDeclaration = 0
 
-          rules(
-            state, emit,
-            // `prefix` ... Hefty. Ugly. Sadly necessary.
-            //
-            (prefix.length > 0 && (/,/.test(prefix) || /,/.test(k))) ?
+          declarations(state, emit, k, v, local);
 
-              /*0*/ (kk = splitSelector(prefix), splitSelector(
-                local ?
+        }
 
-                  k.replace(
-                    /("(?:\\.|[^"\n])*"|'(?:\\.|[^'\n])*'|\/\*[\s\S]*?\*\/)|:global\(\s*(\.-?[_A-Za-z][-\w]*)\s*\)|(\.)(-?[_A-Za-z][-\w]*)/g,
-                    state.L
-                  ) :
+      } else if (/^@/.test(k)) {
+        // Handle At-rules
+        inDeclaration = 0;
 
-                  k
-              ).map(function (k) {
-                return /&/.test(k) ? ampersand(k, kk) : kk.map(function(kk) {
-                  return kk + k
-                }).join(',')
-              }).join(',')) :
+        atRules(state, emit,
+          /^(.(?:-[\w]+-)?([_A-Za-z][-\w]*))\b\s*(.*?)\s*$/.exec(k) || [k,'@','',''],
+          v, prefix, local, nestingDepth
+        );
 
-              /*0*/ /&/.test(k) ?
+      } else {
+        // selector or nested sub-selectors
+        inDeclaration = 0;
 
-                /*1*/ ampersand(
-                  local ?
+        rules(
+          state, emit,
+          // build the selector `prefix` for the next iteration.
+          // ugly and full of redundant bits but so far the fastest/shortest.gz
+          /*0 if*/(prefix.length > 0 && (/,/.test(prefix) || /,/.test(k))) ?
 
-                    k.replace(
-                      /("(?:\\.|[^"\n])*"|'(?:\\.|[^'\n])*'|\/\*[\s\S]*?\*\/)|:global\(\s*(\.-?[_A-Za-z][-\w]*)\s*\)|(\.)(-?[_A-Za-z][-\w]*)/g,
-                      state.L
-                    ) :
+            /*0 then*/ (kk = splitSelector(prefix), splitSelector(
+              local ?
 
-                    k,
-                  [prefix]
+                k.replace(
+                  /("(?:\\.|[^"\n])*"|'(?:\\.|[^'\n])*'|\/\*[\s\S]*?\*\/)|:global\(\s*(\.-?[_A-Za-z][-\w]*)\s*\)|(\.)(-?[_A-Za-z][-\w]*)/g,
+                  state.localizeReplacer
                 ) :
 
-                /*1*/ prefix + (
-                  local ?
+                k
+            ).map(function (k) {
+              return /&/.test(k) ? ampersand(k, kk) : kk.map(function(kk) {
+                return kk + k
+              }).join(',')
+            }).join(',')) :
 
-                    k.replace(
-                      /("(?:\\.|[^"\n])*"|'(?:\\.|[^'\n])*'|\/\*[\s\S]*?\*\/)|:global\(\s*(\.-?[_A-Za-z][-\w]*)\s*\)|(\.)(-?[_A-Za-z][-\w]*)/g,
-                      state.L
-                    ) :
+            /*0 else*/ /*1 if*/ /&/.test(k) ?
 
-                    k
-                  ),
-             v, local, inAtRule
-          )
+              /*1 then*/ ampersand(
+                local ?
 
-        }
-      }
+                  k.replace(
+                    /("(?:\\.|[^"\n])*"|'(?:\\.|[^'\n])*'|\/\*[\s\S]*?\*\/)|:global\(\s*(\.-?[_A-Za-z][-\w]*)\s*\)|(\.)(-?[_A-Za-z][-\w]*)/g,
+                    state.localizeReplacer
+                  ) :
 
-      break
+                  k,
+                [prefix]
+              ) :
 
-    case ARRAY:
-      for (k = 0; k < tree.length; k++){
+              /*1 else*/ prefix + (
+                local ?
 
-        rules(state, emit, prefix, tree[k], local, inAtRule)
+                  k.replace(
+                    /("(?:\\.|[^"\n])*"|'(?:\\.|[^'\n])*'|\/\*[\s\S]*?\*\/)|:global\(\s*(\.-?[_A-Za-z][-\w]*)\s*\)|(\.)(-?[_A-Za-z][-\w]*)/g,
+                    state.localizeReplacer
+                  ) :
 
+                  k
+                ),
+           v, local, nestingDepth + 1
+        );
+
       }
-      break
+    }
 
-    case STRING:
-      // CSS hacks or ouptut of `j2c.inline`.
+    break
 
-      emit.s(prefix.length > 0 ? prefix : ':-error-no-selector')
+  case ARRAY:
+    for (k = 0; k < tree.length; k++){
 
-      declarations(state, emit, '', tree, local)
+      rules(state, emit, prefix, tree[k], local, nestingDepth);
 
     }
-  }
+    break
 
-  // This is the first entry in the filters array, which is
-  // actually the last step of the compiler. It inserts
-  // closing braces to close normal (non at-) rules (those
-  // that start with a selector). Doing it earlier is
-  // impossible without passing state around in unrelated code
-  // or ending up with duplicated selectors when the source tree
-  // contains arrays.
-  // There's no `S` handler, because the core compiler never
-  // calls it.
-  function closeSelectors(next, inline) {
-    var lastSelector
-    return inline ? next : {
-      i: function(){lastSelector = 0; next.i()},
-      x: function (raw) {
-        if (lastSelector) {next.S(); lastSelector = 0}
-        return next.x(raw)
-      },
-      a: function (rule, param, takesBlock) {
-        if (lastSelector) {next.S(); lastSelector = 0}
-        next.a(rule, param, takesBlock)
-      },
-      A: function (rule) {
-        if (lastSelector) {next.S(); lastSelector = 0}
-        next.A(rule)
-      },
-      s: function (selector) {
-        if (selector !== lastSelector){
-          if (lastSelector) next.S()
-          next.s(selector)
-          lastSelector = selector
-        }
-      },
-      d: next.d
-    }
-  }
+  case STRING:
+    // CSS hacks or ouptut of `j2c.inline`.
+    if (!prefix.length) emit.err('No selector');
+    emit.rule(prefix || ' ');
 
-  function global(x) {
-    return ':global(' + x + ')'
-  }
+    declarations(state, emit, '', tree, local);
 
-  function kv (k, v, o) {
-    o = {}
-    o[k] = v
-    return o
   }
+}
 
-  function at (rule, params, block) {
-    if (
-      arguments.length < 3
-    ) {
-      // inner curry!
-      var _at = at.bind.apply(at, [null].concat([].slice.call(arguments,0)))
-      // So that it can be used as a key in an ES6 object literal.
-      _at.toString = function(){return '@' + rule + ' ' + params}
-      return _at
+// This is the first entry in the filters array, which is
+// actually the last step of the compiler. It inserts
+// closing braces to close normal (non at-) rules (those
+// that start with a selector). Doing it earlier is
+// impossible without passing state around in unrelated code
+// or ending up with duplicated selectors when the source tree
+// contains arrays.
+// There's no `_rule` handler, because the core compiler never
+// calls it.
+function closeSelectors(next, inline) {
+  var lastSelector;
+  return inline ? next : {
+    init: function(){lastSelector = 0; next.init();},
+    done: function (raw) {
+      if (lastSelector) {next._rule(); lastSelector = 0;}
+      return next.done(raw)
+    },
+    atrule: function (rule, kind, param, takesBlock) {
+      if (lastSelector) {next._rule(); lastSelector = 0;}
+      next.atrule(rule, kind, param, takesBlock);
+    },
+    _atrule: function (rule) {
+      if (lastSelector) {next._rule(); lastSelector = 0;}
+      next._atrule(rule);
+    },
+    rule: function (selector) {
+      if (selector !== lastSelector){
+        if (lastSelector) next._rule();
+        next.rule(selector);
+        lastSelector = selector;
+      }
     }
-    else return kv('@' + rule +' ' + params, block)
   }
+}
 
-  function j2c() {
+function global(x) {
+  return ':global(' + x + ')'
+}
 
-    // palceholder for the buffer used by the `$sink` handlers
-    var buf
+function kv (k, v, o) {
+  o = {};
+  o[k] = v;
+  return o
+}
 
-    // the bottom of the 'codegen' stream. Mirrors the `$filter` plugin API.
-    var $sink = {
-      // Init
-      i: function(){buf=[]},
-      // done (eXit)
-      x: function (raw) {return raw ? buf : buf.join('')},
-      // start At-rule
-      a: function (rule, argument, takesBlock) {
-        buf.push(rule, argument && ' ',argument, takesBlock ? ' {\n' : ';\n')
-      },
-      // end At-rule
-      A: function ()            {buf.push('}\n')},
-      // start Selector
-      s: function (selector)    {buf.push(selector, ' {\n')},
-      // end Selector
-      S: function ()            {buf.push('}\n')},
-      // declarations
-      d: function (prop, value) {buf.push(prop, prop && ':', value, ';\n')}
-    }
+function at (rule, params, block) {
+  if (
+    arguments.length < 3
+  ) {
+    // inner curry!
+    var _at = at.bind.apply(at, [null].concat([].slice.call(arguments,0)));
+    // So that it can be used as a key in an ES6 object literal.
+    _at.toString = function(){return '@' + rule + ' ' + params};
+    return _at
+  }
+  else return kv('@' + rule +' ' + params, block)
+}
 
-    var $filters = [closeSelectors]
-    var $atHandlers = []
+function j2c() {
 
-    var _instance = {
-      at: at,
-      global: global,
-      kv: kv,
-      names: {},
-      suffix: '__j2c-' +
-        Math.floor(Math.random() * 0x100000000).toString(36) + '-' +
-        Math.floor(Math.random() * 0x100000000).toString(36) + '-' +
-        Math.floor(Math.random() * 0x100000000).toString(36) + '-' +
-        Math.floor(Math.random() * 0x100000000).toString(36),
-      use: function() {
-        _use(emptyArray.slice.call(arguments))
-        return _instance
-      },
-      $plugins: []
-    }
+  // the buffer that accumulates the output. Initialized in `$sink.i()`
+  var buf, err;
 
-    var _streams = []
+  // the bottom of the 'codegen' stream. Mirrors the `$filter` plugin API.
+  var $sink = {
+    init: function(){buf=[], err=[];},
+    done: function (raw) {
+      if (err.length != 0) throw new Error('j2c error(s): ' + JSON.stringify(err,null,2) + 'in context:\n' + buf.join(''))
+      return raw ? buf : buf.join('')
+    },
+    err: function(msg) {
+      err.push(msg);
+      buf.push('/* +++ ERROR +++ ' + msg + ' */\n');
+    },
+    atrule: function (rule, kind, param, takesBlock) {
+      buf.push(rule, param && ' ', param, takesBlock ? ' {' : ';', _instance.endline);
+    },
+    // close atrule
+    _atrule: function () {buf.push('}', _instance.endline);},
+    rule: function (selector) {buf.push(selector, ' {', _instance.endline);},
+    // close rule
+    _rule: function () {buf.push('}', _instance.endline);},
+    decl: function (prop, value) {buf.push(prop, prop && ':', value, ';', _instance.endline);}
+  };
 
-    // The `state` (for the core) / `walker` (for the plugins) tables.
+  // holds the `$filter` and `$at` handlers
+  var $filters = [closeSelectors];
+  var $atHandlers = [];
 
-    var _walkers = [
-      // for j2c.sheet
-      {
-        // helpers for locaizing class and animation names
-        L: _localizeReplacer, // second argument to String.prototype.replace
-        l: _localize,         // mangles local names
-        n: _instance.names,    // local => mangled mapping
-        $a: $atHandlers,      // extra at-rules
-        // The core walker methods, to be provided to plugins
-        a: atRules,
-        d: declarations,
-        r: rules
-      },
-      // likewise, for j2c.inline (idem with `$a`, `a` and `s` removed)
-      {
-        L: _localizeReplacer,
-        l: _localize,
-        n: _instance.names,
-        d: declarations
-      }
-    ]
-
-
-    // The main API functions
-
-    _instance.sheet = function(tree) {
-      var emit = _getStream(0)
-      emit.i()
+  // the public API (see the main docs)
+  var _instance = {
+    at: at,
+    global: global,
+    kv: kv,
+    names: {},
+    endline: '\n',
+    suffix: '__j2c-' +
+      // 128 bits of randomness
+      Math.floor(Math.random() * 0x100000000).toString(36) + '-' +
+      Math.floor(Math.random() * 0x100000000).toString(36) + '-' +
+      Math.floor(Math.random() * 0x100000000).toString(36) + '-' +
+      Math.floor(Math.random() * 0x100000000).toString(36),
+    $plugins: [],
+    sheet: function(tree) {
+      var emit = _createOrRetrieveStream(0);
+      emit.init();
       rules(
         _walkers[0],
         emit,
-        '',    // prefix
+        '', // prefix
         tree,
-        1,      // local, by default
-        0     // inAtRule
-      )
+        1,  // local, by default
+        0   // nesting depth
+      );
 
-      return emit.x()
-    }
-
-    _instance.inline = function (tree) {
-      var emit = _getStream(1)
-      emit.i()
+      return emit.done()
+    },
+    inline: function (tree, options) {
+      var emit = _createOrRetrieveStream(1);
+      emit.init();
       declarations(
         _walkers[1],
         emit,
-        '',         // prefix
+        '', // prefix
         tree,
-        1           //local
-      )
-      return emit.x()
+        !(options && options.global)   // local, by default
+      );
+      return emit.done()
     }
+  };
 
-    // inner helpers
+  // The `state` (for the core functions) / `walker` (for the plugins) tables.
+  var _walkers = [
+    // for j2c.sheet
+    {
+      // helpers for locaizing class and animation names
+      localizeReplacer: _localizeReplacer, // second argument to String.prototype.replace
+      localize: _localize,                 // mangles local names
+      names: _instance.names,              // local => mangled mapping
+      $atHandlers: $atHandlers,            // extra at-rules
+      // The core walker methods, to be provided to plugins
+      atrule: atRules,
+      decl: declarations,
+      rule: rules
+    },
+    // likewise, for j2c.inline (idem with `$a`, `a` and `s` removed)
+    {
+      localizeReplacer: _localizeReplacer,
+      localize: _localize,
+      names: _instance.names,
+      decl: declarations
+    }
+  ];
 
-    var _use = flatIter(function(plugin) {
-      // `~n` is falsy for `n === -1` and truthy otherwise.
-      // Works well to turn the  result of `a.indexOf(x)`
-      // into a value that reflects the presence of `x` in
-      // `a`.
-      if (~_instance.$plugins.indexOf(plugin)) return
 
-      _instance.$plugins.push(plugin)
+  // inner helpers
 
-      if (type.call(plugin) === FUNCTION) plugin = plugin(_instance)
+  var _use = flatIter(function(plugin) {
+    // `~n` is falsy for `n === -1` and truthy otherwise.
+    // Works well to turn the  result of `a.indexOf(x)`
+    // into a value that reflects the presence of `x` in
+    // `a`.
+    if (~_instance.$plugins.indexOf(plugin)) return
 
-      if (!plugin) return
+    _instance.$plugins.push(plugin);
 
-      flatIter(function(filter) {
-        $filters.push(filter)
-      })(plugin.$filter || emptyArray)
+    if (type.call(plugin) === FUNCTION) plugin = plugin(_instance);
 
-      flatIter(function(handler) {
-        $atHandlers.push(handler)
-      })(plugin.$at || emptyArray)
+    if (!plugin) return
 
-      Default(_instance.names, plugin.$names || emptyObject)
+    flatIter(function(filter) {
+      $filters.push(filter);
+    })(plugin.$filter || emptyArray);
 
-      _use(plugin.$plugins || emptyArray)
+    flatIter(function(handler) {
+      $atHandlers.push(handler);
+    })(plugin.$at || emptyArray);
 
-      $sink = plugin.$sink || $sink
+    defaults(_instance.names, plugin.$names || emptyObject);
 
-      Default(_instance, plugin)
-    })
+    _use(plugin.$plugins || emptyArray);
 
-    function _getStream(inline) {
-      if (!_streams.length) {
-        for(var i = 0; i < 2; i++){
-          $filters[$filters.length - i] = function(_, inline) {return inline ? {i:$sink.i, d:$sink.d, x:$sink.x} : $sink}
-          for (var j = $filters.length; j--;) {
-            _streams[i] = freeze(Default(
-              $filters[j](_streams[i], !!i, _walkers[i]),
+    $sink = plugin.$sink || $sink;
+
+    defaults(_instance, plugin);
+  });
+
+
+  var _streams = [];
+  /**
+   * returns the codegen streams, creating them if necessary
+   * @param
+   */
+  function _createOrRetrieveStream(inline) {
+    // build the stream processors if needed
+    if (!_streams.length) {
+      // append the $sink as the ultimate filter
+      $filters.push(function(_, inline) {return inline ? {init:$sink.init, decl:$sink.decl, done:$sink.done, err: $sink.err} : $sink});
+      for(var i = 0; i < 2; i++){ // 0 for j2c.sheet, 1 for j2c.inline
+        for (var j = $filters.length; j--;) {
+          _streams[i] = freeze(
+            defaults(
+              $filters[j](_streams[i], !!i),
               _streams[i]
-            ))
-          }
+            )
+          );
         }
       }
-      var res = _streams[inline]
-      return res
     }
+    return _streams[inline]
+  }
 
-    function _localize(name) {
-      if (!_instance.names[name]) _instance.names[name] = name + _instance.suffix
-      return _instance.names[name].match(/^\S+/)
-    }
+  /**
+   * Returns a localized version of a given name.
+   * Registers the pair in `instnace.name` if needed.
+   *
+   * @param {string} name - the name to localize
+   * @return {string} - the localized version
+   */
+  function _localize(name) {
+    if (!_instance.names[name]) _instance.names[name] = name + _instance.suffix;
+    return _instance.names[name].match(/^\S+/)
+  }
 
-    function _localizeReplacer(match, string, global, dot, name) {
-      if (string || global) return string || global
-      return dot + _localize(name)
-    }
-
-    return _instance
+  /**
+   * Used as second argument for str.replace(localizeRegex, replacer)
+   * `ignore`, `global` and `(dot, name)` are mutually exclusive
+   *
+   * @param {string} match - the whole match (ignored)
+   * @param {string|null} ignore - a comment or a string literal
+   * @param {string|null} global - a global name
+   * @param {string|null} dot - either '.' for a local class name or the empty string otherwise
+   * @param {string|null} name - the name to localize
+   * @return {string}
+   */
+  function _localizeReplacer(match, ignore, global$$1, dot, name) {
+    return ignore || global$$1 || dot + _localize(name)
   }
 
-  var _j2c = j2c()
-  'sheet|inline|names|at|global|kv|suffix'.split('|').map(function(m){j2c[m] = _j2c[m]})
+  _use(emptyArray.slice.call(arguments));
+  return _instance
+}
 
-  return j2c;
+return j2c;
 
-}());
+}());

dist/j2c.global.min.js

@@ -1,1 +0,1 @@
-var j2c=function(){"use strict";function n(n,t){for(var e in t)S.call(t,e)&&(!e.indexOf("$")||e in n||(n[e]=t[e]));return n}function t(n,t){var e,r,a=[];for(r in t)if(S.call(t,r))for(e in n)S.call(n,e)&&a.push(n[e]+t[r]);return a}function e(n){for(var t,e=[],r=[],a=0;t=x.exec(n);)switch(t[0]){case"(":a++;break;case")":a--;break;case",":if(a)break;e.push(t.index)}for(t=e.length;t--;)r.unshift(n.slice(e[t]+1)),n=n.slice(0,e[t]);return r.unshift(n),r}function r(n,e){for(var r,a,i=[],s=[];a=_.exec(n);)"&"==a[0]&&i.push(a.index);for(a=i.length;a--;)s.unshift(n.slice(i[a]+1)),n=n.slice(0,i[a]);for(s.unshift(n),r=[s[0]],a=1;a<s.length;a++)r=t(r,t(e,[s[a]]));return r.join(",")}function a(n){return function t(e){if(d.call(e)===$)for(var r=0;r<e.length;r++)t(e[r]);else n(e)}}function i(n){return"-"+n.toLowerCase()}function s(n,t,e,r,a){var o,l,u;if(null!=r)switch(d.call(r=r.valueOf())){case $:for(o=0;o<r.length;o++)s(n,t,e,r[o],a);break;case v:e=e&&e+"-";for(o in r)if(S.call(r,o))if(l=r[o],/\$/.test(o))for(u in o=o.split("$"))S.call(o,u)&&s(n,t,e+o[u],l,a);else s(n,t,e+o,l,a);break;default:o=e.replace(/_/g,"-").replace(/[A-Z]/g,i),!a||"animation-name"!=o&&"animation"!=o&&"list-style"!=o||(r=r.split(",").map(function(t){return t.replace(/(var\([^)]+\))|:?global\(\s*([_A-Za-z][-\w]*)\s*\)|()(-?[_A-Za-z][-\w]*)/,n.L)}).join(",")),t.d(o,r)}}function o(n,t,e,r,i,o,u){for(var f=0;f<n.$a.length;f++)if(n.$a[f](n,t,e,r,i,o,u))return;if(!e[3]&&/^global$/.test(e[2]))l(n,t,i,r,0,u);else if(!e[3]&&/^local$/.test(e[2]))l(n,t,i,r,1,u);else if(e[3]&&/^adopt$/.test(e[2])){if(!o||u)return t.a("@-error-bad-at-adopt-placement",JSON.stringify(e[0]),0);if(!/^\.?[_A-Za-z][-\w]*$/.test(e[3]))return t.a("@-error-bad-at-adopter",e[3],0);f=[],a(function(n,e){/^\.?[_A-Za-z][-\w]*(?:\s+\.?[_A-Za-z][-\w]*)*$/.test(e=n.toString())?f.push(e.replace(/\./g,"")):t.a("@-error-bad-at-adoptee",JSON.stringify(n),0)})(r),f.length&&(n.l(e[3]=e[3].replace(/\./g,"")),n.n[e[3]]+=" "+f.join(" "))}else!e[3]&&/^(?:namespace|import|charset)$/.test(e[2])?a(function(n){t.a(e[0],n)})(r):!e[3]&&/^(?:font-face|viewport)$/.test(e[2])?a(function(r){t.a(e[1],"",1),s(n,t,"",r,o),t.A(e[1],"")})(r):e[3]&&/^(?:media|supports|page|keyframes)$/.test(e[2])?(o&&"keyframes"==e[2]&&(e[3]=e[3].replace(/(var\([^)]+\))|:?global\(\s*([_A-Za-z][-\w]*)\s*\)|()(-?[_A-Za-z][-\w]*)/,n.L)),t.a(e[1],e[3],1),"page"==e[2]?s(n,t,"",r,o):l(n,t,"keyframes"==e[2]?"":i,r,o,1),t.A(e[1],e[3])):t.a("@-error-unsupported-at-rule",JSON.stringify(e[0]))}function l(n,t,a,i,u,f){var c,g,p,h;switch(d.call(i)){case v:for(c in i)if(S.call(i,c))if(g=i[c],a.length>0&&/^[-\w$]+$/.test(c))if(p||(p=1,t.s(a)),/\$/.test(c))for(h in c=c.split("$"))S.call(c,h)&&s(n,t,c[h],g,u);else s(n,t,c,g,u);else/^@/.test(c)?(p=0,o(n,t,/^(.(?:-[\w]+-)?([_A-Za-z][-\w]*))\b\s*(.*?)\s*$/.exec(c)||[c,"@","",""],g,a,u,f)):(p=0,l(n,t,a.length>0&&(/,/.test(a)||/,/.test(c))?(h=e(a),e(u?c.replace(/("(?:\\.|[^"\n])*"|'(?:\\.|[^'\n])*'|\/\*[\s\S]*?\*\/)|:global\(\s*(\.-?[_A-Za-z][-\w]*)\s*\)|(\.)(-?[_A-Za-z][-\w]*)/g,n.L):c).map(function(n){return/&/.test(n)?r(n,h):h.map(function(t){return t+n}).join(",")}).join(",")):/&/.test(c)?r(u?c.replace(/("(?:\\.|[^"\n])*"|'(?:\\.|[^'\n])*'|\/\*[\s\S]*?\*\/)|:global\(\s*(\.-?[_A-Za-z][-\w]*)\s*\)|(\.)(-?[_A-Za-z][-\w]*)/g,n.L):c,[a]):a+(u?c.replace(/("(?:\\.|[^"\n])*"|'(?:\\.|[^'\n])*'|\/\*[\s\S]*?\*\/)|:global\(\s*(\.-?[_A-Za-z][-\w]*)\s*\)|(\.)(-?[_A-Za-z][-\w]*)/g,n.L):c),g,u,f));break;case $:for(c=0;c<i.length;c++)l(n,t,a,i[c],u,f);break;case b:t.s(a.length>0?a:":-error-no-selector"),s(n,t,"",i,u)}}function u(n,t){var e;return t?n:{i:function(){e=0,n.i()},x:function(t){return e&&(n.S(),e=0),n.x(t)},a:function(t,r,a){e&&(n.S(),e=0),n.a(t,r,a)},A:function(t){e&&(n.S(),e=0),n.A(t)},s:function(t){t!==e&&(e&&n.S(),n.s(t),e=t)},d:n.d}}function f(n){return":global("+n+")"}function c(n,t,e){return e={},e[n]=t,e}function g(n,t,e){if(arguments.length<3){var r=g.bind.apply(g,[null].concat([].slice.call(arguments,0)));return r.toString=function(){return"@"+n+" "+t},r}return c("@"+n+" "+t,e)}function p(){function t(t){if(!S.length)for(var e=0;2>e;e++){$[$.length-e]=function(n,t){return t?{i:p.i,d:p.d,x:p.x}:p};for(var r=$.length;r--;)S[e]=A(n($[r](S[e],!!e,x[e]),S[e]))}var a=S[t];return a}function e(n){return b.names[n]||(b.names[n]=n+b.suffix),b.names[n].match(/^\S+/)}function r(n,t,r,a,i){return t||r?t||r:a+e(i)}var i,p={i:function(){i=[]},x:function(n){return n?i:i.join("")},a:function(n,t,e){i.push(n,t&&" ",t,e?" {\n":";\n")},A:function(){i.push("}\n")},s:function(n){i.push(n," {\n")},S:function(){i.push("}\n")},d:function(n,t){i.push(n,n&&":",t,";\n")}},$=[u],v=[],b={at:g,global:f,kv:c,names:{},suffix:"__j2c-"+Math.floor(4294967296*Math.random()).toString(36)+"-"+Math.floor(4294967296*Math.random()).toString(36)+"-"+Math.floor(4294967296*Math.random()).toString(36)+"-"+Math.floor(4294967296*Math.random()).toString(36),use:function(){return _(h.slice.call(arguments)),b},$plugins:[]},S=[],x=[{L:r,l:e,n:b.names,$a:v,a:o,d:s,r:l},{L:r,l:e,n:b.names,d:s}];b.sheet=function(n){var e=t(0);return e.i(),l(x[0],e,"",n,1,0),e.x()},b.inline=function(n){var e=t(1);return e.i(),s(x[1],e,"",n,1),e.x()};var _=a(function(t){~b.$plugins.indexOf(t)||(b.$plugins.push(t),d.call(t)===w&&(t=t(b)),t&&(a(function(n){$.push(n)})(t.$filter||h),a(function(n){v.push(n)})(t.$at||h),n(b.names,t.$names||m),_(t.$plugins||h),p=t.$sink||p,n(b,t)))});return b}var h=[],m={},d=m.toString,$=d.call(h),v=d.call(m),b=d.call(""),w=d.call(d),S=m.hasOwnProperty,A=Object.freeze||function(n){return n},x=/[(),]|"(?:\\.|[^"\n])*"|'(?:\\.|[^'\n])*'|\/\*[\s\S]*?\*\//g,_=/&|"(?:\\.|[^"\n])*"|'(?:\\.|[^'\n])*'|\/\*[\s\S]*?\*\//g,z=p();return"sheet|inline|names|at|global|kv|suffix".split("|").map(function(n){p[n]=z[n]}),p}();
+var j2c=function(){"use strict";function e(e,n){for(var t in n)b.call(n,t)&&(!t.indexOf("$")||t in e||(e[t]=n[t]));return e}function n(e,n){var t,r,l=[];for(r in n)if(b.call(n,r))for(t in e)b.call(e,t)&&l.push(e[t]+n[r]);return l}function t(e){for(var n,t=[],r=[],l=0;n=A.exec(e);)switch(n[0]){case"(":l++;break;case")":l--;break;case",":if(l)break;t.push(n.index)}for(n=t.length;n--;)r.unshift(e.slice(t[n]+1)),e=e.slice(0,t[n]);return r.unshift(e),r}function r(e,t){for(var r,l,a=[],i=[];l=S.exec(e);)"&"==l[0]&&a.push(l.index);for(l=a.length;l--;)i.unshift(e.slice(a[l]+1)),e=e.slice(0,a[l]);for(i.unshift(e),1===i.length&&i.unshift(""),r=[i[0]],l=1;l<i.length;l++)r=n(r,n(t,[i[l]]));return r.join(",")}function l(e){return function n(t){if(m.call(t)===$)for(var r=0;r<t.length;r++)n(t[r]);else e(t)}}function a(e){return"-"+e.toLowerCase()}function i(e,n,t,r,l){var o,u,c;if(null!=r)switch(m.call(r=r.valueOf())){case $:for(o=0;o<r.length;o++)i(e,n,t,r[o],l);break;case _:t=t&&t+"-";for(o in 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i(e,n,f,p,c);else/^@/.test(f)?(h=0,o(e,n,/^(.(?:-[\w]+-)?([_A-Za-z][-\w]*))\b\s*(.*?)\s*$/.exec(f)||[f,"@","",""],p,l,c,s)):(h=0,u(e,n,l.length>0&&(/,/.test(l)||/,/.test(f))?(g=t(l),t(c?f.replace(/("(?:\\.|[^"\n])*"|'(?:\\.|[^'\n])*'|\/\*[\s\S]*?\*\/)|:global\(\s*(\.-?[_A-Za-z][-\w]*)\s*\)|(\.)(-?[_A-Za-z][-\w]*)/g,e.localizeReplacer):f).map(function(e){return/&/.test(e)?r(e,g):g.map(function(n){return n+e}).join(",")}).join(",")):/&/.test(f)?r(c?f.replace(/("(?:\\.|[^"\n])*"|'(?:\\.|[^'\n])*'|\/\*[\s\S]*?\*\/)|:global\(\s*(\.-?[_A-Za-z][-\w]*)\s*\)|(\.)(-?[_A-Za-z][-\w]*)/g,e.localizeReplacer):f,[l]):l+(c?f.replace(/("(?:\\.|[^"\n])*"|'(?:\\.|[^'\n])*'|\/\*[\s\S]*?\*\/)|:global\(\s*(\.-?[_A-Za-z][-\w]*)\s*\)|(\.)(-?[_A-Za-z][-\w]*)/g,e.localizeReplacer):f),p,c,s+1));break;case $:for(f=0;f<a.length;f++)u(e,n,l,a[f],c,s);break;case z:l.length||n.err("No selector"),n.rule(l||" "),i(e,n,"",a,c)}}function c(e,n){var t;return n?e:{init:function(){t=0,e.init()},done:function(n){return t&&(e._rule(),t=0),e.done(n)},atrule:function(n,r,l,a){t&&(e._rule(),t=0),e.atrule(n,r,l,a)},_atrule:function(n){t&&(e._rule(),t=0),e._atrule(n)},rule:function(n){n!==t&&(t&&e._rule(),e.rule(n),t=n)}}}function s(e){return":global("+e+")"}function f(e,n,t){return t={},t[e]=n,t}function p(e,n,t){if(arguments.length<3){var r=p.bind.apply(p,[null].concat([].slice.call(arguments,0)));return r.toString=function(){return"@"+e+" "+n},r}return f("@"+e+" "+n,t)}function h(){function n(n){if(!Z.length){_.push(function(e,n){return n?{init:$.init,decl:$.decl,done:$.done,err:$.err}:$});for(var t=0;t<2;t++)for(var r=_.length;r--;)Z[t]=v(e(_[r](Z[t],!!t),Z[t]))}return Z[n]}function t(e){return b.names[e]||(b.names[e]=e+b.suffix),b.names[e].match(/^\S+/)}function r(e,n,r,l,a){return n||r||l+t(a)}var a,h,$={init:function(){a=[],h=[]},done:function(e){if(0!=h.length)throw new Error("j2c error(s): "+JSON.stringify(h,null,2)+"in context:\n"+a.join(""));return e?a:a.join("")},err:function(e){h.push(e),a.push("/* +++ ERROR +++ "+e+" */\n")},atrule:function(e,n,t,r){a.push(e,t&&" ",t,r?" {":";",b.endline)},_atrule:function(){a.push("}",b.endline)},rule:function(e){a.push(e," {",b.endline)},_rule:function(){a.push("}",b.endline)},decl:function(e,n){a.push(e,e&&":",n,";",b.endline)}},_=[c],z=[],b={at:p,global:s,kv:f,names:{},endline:"\n",suffix:"__j2c-"+Math.floor(4294967296*Math.random()).toString(36)+"-"+Math.floor(4294967296*Math.random()).toString(36)+"-"+Math.floor(4294967296*Math.random()).toString(36)+"-"+Math.floor(4294967296*Math.random()).toString(36),$plugins:[],sheet:function(e){var t=n(0);return t.init(),u(A[0],t,"",e,1,0),t.done()},inline:function(e,t){var r=n(1);return r.init(),i(A[1],r,"",e,!(t&&t.global)),r.done()}},A=[{localizeReplacer:r,localize:t,names:b.names,$atHandlers:z,atrule:o,decl:i,rule:u},{localizeReplacer:r,localize:t,names:b.names,decl:i}],S=l(function(n){~b.$plugins.indexOf(n)||(b.$plugins.push(n),m.call(n)===w&&(n=n(b)),n&&(l(function(e){_.push(e)})(n.$filter||g),l(function(e){z.push(e)})(n.$at||g),e(b.names,n.$names||d),S(n.$plugins||g),$=n.$sink||$,e(b,n)))}),Z=[];return S(g.slice.call(arguments)),b}var g=[],d={},m=d.toString,$=m.call(g),_=m.call(d),z=m.call(""),w=m.call(m),b=d.hasOwnProperty,v=Object.freeze||function(e){return e},A=/[(),]|"(?:\\.|[^"\n])*"|'(?:\\.|[^'\n])*'|\/\*[\s\S]*?\*\//g,S=/&|"(?:\\.|[^"\n])*"|'(?:\\.|[^'\n])*'|\/\*[\s\S]*?\*\//g;return h}();

HISTORY.md

@@ -5,24 +5,2 @@ # Change log
 
-
-- Fix: Robust parsing of selectors. Comas, ampersands and class-like parts
-  in strings are now ignored by the compiler.
-
-  ```JS
-  j2c.sheet({'p':{'[foo="&,.bar"]': {color: 'red'}}})
-  ```
-
-  produces
-
-  ```CSS
-  p[foo="&,.bar"] {color:red}
-  ```
-
-  Whereas previous versions would produce
-
-  ```CSS
-  [foo="p,p.bar_j2c_ubv4pc_knzcqw_ngjme7_1usit1c_9"] {color: red;}
-  ```
-
-  Likewise, `':not(p, a, ul, li)'` (a CSS4 addition) will not be split.
-  
 - Local scope is now per instance rather than per sheet.
@@ -47,4 +25,6 @@ - `j2c.sheet()` and `j2c.inline()` return plain strings rather than
 
-  So: `j2c.sheet({'@adopt .foo': ['.bar']})` where foo is a local class that adopts the behavior of the global `.bar`.
-- Consecutive, identical selectors are deduped in the output.
+  So: `j2c.sheet({'@adopt .foo': ['.bar']})` where foo is a local class that
+  adopts the behavior of the global `.bar`.
+- Consecutive, identical selectors are deduped in the output. Using mixins
+  won't cause duplicate selectors anymore.
 - Prefixed at-rules are treated like their unprefixed counterparts.
@@ -55,19 +35,46 @@ - Added the `at()`, `global()` and `kv()` helpers.
   like SASS and LESS do.
+- Robust parsing of selectors. Comas, ampersands and class-like parts
+  in strings are now ignored by the compiler.
+
+  ```JS
+  j2c.sheet({'p':{'[foo="&,.bar"]': {color: 'red'}}})
+  ```
+
+  produces
+
+  ```CSS
+  p[foo="&,.bar"] {color:red}
+  ```
+
+  Whereas previous versions would produce
+
+  ```CSS
+  [foo="p,p.bar_j2c_ubv4pc_knzcqw_ngjme7_1usit1c_9"] {color: red;}
+  ```
+
+  Likewise, `':not(p, a, ul, li)'` (a CSS4 addition) will not be split.
+- Added an extension mechanism.
 - 2.2Kb mingzipped (+ ~500 bytes).
 
-## v0.11.1 (2016-03-8)
+## v0.11.1 (2016-03-8) and v0.11.2 (2016-03-17)
 
-- Patch bump to fix what `npm` installs by default (I erronously published `v1.0.0-0` on without `--tag next`)
+- Patch bump to fix what `npm` installs by default (I erronously published `
+  v1.0.0-x` on without `--tag next`, twice) Note to self, don't publish in
+  the wee hours.
 
 ## v0.11.0
 
-- Refactor the innards so that the source order is completely respected in the output, including conditional at-rules.
+- Refactor the innards so that the source order is completely respected in
+  the output, including conditional at-rules.
 - Speed ++
 - Autoprefix all animation-* and transition.
-- Some error messages are now inserted in the result as -error-prefixed at-rules and :pseudo-classes.
+- Some error messages are now inserted in the result as -error-prefixed
+  at-rules and :pseudo-classes.
 
 ## v0.10.0
 
-- At long last allow element selectors without a prepended space at the top level
-- Autoprefix animation and animation-name with -webkit- too like we do for `@keyframes`.
+- At long last allow element selectors without a prepended space at the top
+  level
+- Autoprefix animation and animation-name with -webkit- too like we do for
+  `@keyframes`.
 - Tweaks and cleanup
@@ -97,3 +104,4 @@
 
-- classes and animations/@keyframes names are now localized by default in `j2c.sheet()`.
+- classes and animations/@keyframes names are now localized by default in
+  `j2c.sheet()`.
 - introduced `@global{}` and `:global()` to reach global names
@@ -104,11 +112,15 @@ - dropped `j2c.scoped()` which is obsoleted by the above.
 - support for autoDeCamelization of property-names.
-- New signature for `j2c.sheet([namespace1, namespace2, ] source)` where `namespace` is an object
-with plain -> localized names for classes and animations.
-- allow to create custom j2c instances that can be extended with plugins *[needs docs]*.
+- New signature for `j2c.sheet([namespace1, namespace2, ] source)` where
+  `namespace` is an object with plain -> localized names for classes and
+  animations.
+- allow to create custom j2c instances that can be extended with plugins
+  *[needs docs]*.
 - Hardened the test suite.
-- Bug fix: the source order is now respected in the output, with the caveat that, for nested selector, the children appear in source before the parent.
+- Bug fix: the source order is now respected in the output, with the caveat
+  that, for nested selector, the children appear in source before the parent.
 
 ## v0.7.3
 
-- Identical to `v0.7.2`. Somehow a bad commit ended up on NPM for that version.
+- Identical to `v0.7.2`. Somehow a bad commit ended up on NPM for that
+  version.
 
@@ -115,0 +127,0 @@ ## v0.7.2

package.json

 {
   "name": "j2c",
-  "version": "1.0.0-3",
+  "version": "1.0.0-4",
   "description": "A tiny CSS in JS solution.",
   "main": "dist/j2c.commonjs.js",
   "scripts": {
-    "preversion": "npm run all",
+    "preversion": "yarn run all",
     "prepublish": "(in-publish && git push --follow-tags) || not-in-publish",
-    "all": "npm run build && npm run lint && npm run cover",
-    "dev": "npm run build && npm run test",
+    "all": "yarn run build && yarn run lint && yarn run cover",
+    "dev": "yarn run build && yarn run test",
     "build": "rm -f dist/*.js && node scripts/build.js",
-    "lint": "eslint --fix src/*.js test/test.js scripts/*.js",
-    "test": "mocha --ui qunit",
-    "cover": "istanbul cover _mocha -- -R nyan --ui qunit && npm run -s check-coverage",
+    "lint": "eslint --fix .",
+    "test": "ospec",
+    "cover": "istanbul cover --print both node_modules/.bin/ospec && yarn run check-coverage",
     "check-coverage": "istanbul check-coverage --branches -2",
-    "travis": "npm run build && istanbul cover _mocha --report lcovonly -- -R spec --ui qunit && (codecov || true) && npm run -s check-coverage"
+    "travis": "yarn run build && istanbul cover --print both node_modules/.bin/ospec && (codecov || true) && yarn run  check-coverage"
   },
@@ -33,12 +33,11 @@ "repository": {
   "devDependencies": {
+    "cash-true": "0.0.2",
     "codecov": "^1.0.1",
-    "commonmark": "^0.24.0",
+    "commonmark": "^0.27.0",
     "compose-regexp": "^0.1.8",
-    "eslint": "^2.2.0",
-    "expect.js": "0.3.1",
+    "eslint": "^3.12.0",
     "in-publish": "^2.0.0",
     "istanbul": "^0.4.2",
-    "jsdom": "^8.1.0",
-    "mocha": "^2.3.4",
-    "mocha-lcov-reporter": "^1.0.0",
+    "jsdom": "^9.8.3",
+    "ospec": "^1.2.1",
     "perfectionist": "^2.1.2",
@@ -48,6 +47,6 @@ "postcss": "^5.0.14",
     "postcss-minify-selectors": "^2.0.2",
-    "rollup": "^0.25.2",
-    "surgicate": "0.0.3",
-    "uglify-js": "^2.6.0"
+    "rollup": "^0.36.4",
+    "uglify-js": "^2.6.0",
+    "yarn": "^0.18.1"
   }
 }

PLUGINS.md

 # `j2c` Plugin author notes
 
-A plugin can be an object, a function or an array of plugins (nested arrays are thus supported).
+Out of the box, `j2c` is made of a frontend that walks a JS objets/arrays tree and calls the backend when necessary to emit atrules, rules and declarations.
 
+The default backend fills a buffer with strings and `joins` them on completion.
+
+`j2c` plugin can either tap into the frontend (by implementing custom at-rules), replace the backend, and insert middleware filters in between.
+
+We'll process backwards and start by describing the backend, since understanding how it works is required to write filters and useful to write custom at-rules.
+
+## `$sink` plugins: replace the backend
+
+
+A `j2c` backend mus provide the following API:
+
 ```JS
-_j2c = j2c().use(
+{
+    init() {},
+    // called on `j2c.sheet()/j2c.inline()` invocations before 
+    // the sheet is processed.
+    done() {},
+    // called when the tree traversal is finished, to finalize
+    // the style sheet
+    err(message) {},
+    // called when an error is noticed, allows to display errors
+    // in context.
+    decl(property, value),
+    // called to insert a declaration into the sheet
+    rule(selector) {},
+    // called to open a rule with a given selector
+    _rule() {},
+    // called to signal the end of a ruleset
+    atrule(rule, kind, param, takesBlock)
+    // called when an atrule is encountered.
+    // `rule` is the rule name in full includin the '@' and the
+    // prefix when there's one. e.g. `@-webkit-keyframes`
+    // `kind` is the type of at-rule, without '@' nor prefix
+    // e.g. `keyframes`
+    // `param` is the optional parameter
+    // `takesBlock` is a boolean that tells whether the rule 
+    // takes a block or not. false for `@namespace`, `@charset`
+    // and `@import`, true otherwise.
+    _atrule(){}
+    // called to signal the end of an atrule block
+}
+```
+
+`j2c.inline()` uses the same API but restricted to `init()`, `done()`, `err(msg)` and `decl(property, value)`.
+
+A plugin can be an object, a function or an array of zero or plugins (nested arrays are thus supported).
+
+```JS
+_j2c = j2c(
     {foo: 1}, 
@@ -8,0 +55,0 @@ [

README.md

@@ -12,2 +12,3 @@ # Warning, WIP: these docs haven't been updated to match the changes since v0.11
 [![bitHound Score][bithound_img]][bithound_url]
+[![downloads][monthly_img]][monthly_url]
 
@@ -29,3 +30,3 @@ [trav_img]: https://travis-ci.org/j2css/j2c.svg?branch=master
 
-A lean (2.0KB), no hassle CSS in JS solution.
+A lean (2.2KB), no hassle CSS in JS solution.
 
@@ -75,2 +76,3 @@ `j2c`:
 
+
 ### `j2c` is mostly done.
@@ -86,3 +88,3 @@
 - @ArthurClemens, @StephanHoyer, @der-On, @llambda, @dontwork, @futurist and @mithriljs-cn for the support and feedback.
-- @tivac for `@compose` which I stole from his [Modular CSS]() project.
+- @tivac for `compose` which I stole from his [Modular CSS]() project.
 
@@ -93,3 +95,3 @@ ## Table of Contents
 - [Usage](#usage)
-  - [For inline decalrations: `j2c.inline(declarations)`](#for-inline-decalrations-j2cinlinedeclarations)
+  - [For inline declarations: `j2c.inline(declarations)`](#for-inline-declarations-j2cinlinedeclarations)
     - [Arrays](#arrays)
@@ -180,3 +182,3 @@ - [Overloading properties](#overloading-properties)
 
-### For inline decalrations: `j2c.inline(declarations)`
+### For inline declarations: `j2c.inline(declarations)`
 
@@ -209,3 +211,3 @@ The `j2c` function takes in JS objects and builds a `property:value;` list out of it.
 
-Combine (sub)properties who share the same value using `$` as a separator. It is useful to specify vendor prefixes.
+Combine (sub)properties who share the same value by using `$` as a separator. It is useful to specify vendor prefixes.
 
@@ -378,3 +380,3 @@ #### Property ordering
   ".block,.blockgroup":{
-    ",:before,:after":{          // Notice the initial coma.
+    ",:before,:after":{          // Notice the initial comma.
       box_sizing:"border-box"
@@ -647,6 +649,5 @@ }
         return m("style", {
-            sheet: args.sheet
-            config: function(el, isinit, vdom) {
+            config: function(el, isinit) {
                 if(!isinit) {
-                    stylize(el, vdom.attrs.sheet);
+                    stylize(el, args.sheet);
                 }
@@ -653,0 +654,0 @@ }

scripts/build.js

@@ -28,3 +28,3 @@ #! /usr/bin/env node
       rollupOptions:{
-        format: 'es6'
+        format: 'es'
       },
@@ -31,0 +31,0 @@ name: 'es6',

scripts/regexps.js

 /*eslint-env node*/
 /*eslint no-console: 0*/
-/*eslint no-undef: 0*/
-
+/* global capture: false, either:false, flags: false, greedy:false, sequence: false*/
 global.__proto__ = require('compose-regexp')
 
-var maybe = greedy.bind(null, '?')
-maybe()
+// var maybe = greedy.bind(null, '?')
 
 var animation = either(
+    capture(
+        'var(',
+        /[^)]+/,
+        ')'
+    ),
     sequence(
@@ -26,18 +29,51 @@ /:?/,
 
-var selector = flags('g', either(
-    sequence(
-        ':global(',
-        /\s*/,
+var selector = flags('g',
+    either(
         capture(
-            '.',
-            /-?[_A-Za-z][-\w]*/
+            either(
+                sequence(
+                    '"',
+                    greedy('*',
+                        either(
+                            /\\./,
+                            /[^"\n]/
+                        )
+                    ),
+                    '"'
+                ),
+                sequence(
+                    "'",
+                    greedy('*',
+                        either(
+                            /\\./,
+                            /[^'\n]/
+                        )
+                    ),
+                    "'"
+                ),
+                // This is both correct and faster than the W3C regexp.
+                // https://jsperf.com/regexpcomment
+                sequence(
+                    '/*',
+                    /[\s\S]*?/,
+                    '*/'
+                )
+            )
         ),
-        /\s*/,
-        ')'
-    ),
-    sequence(
-        capture('.'),
-        capture(/-?[_A-Za-z][-\w]*/)
+        sequence(
+            ':global(',
+            /\s*/,
+            capture(
+                '.',
+                /-?[_A-Za-z][-\w]*/
+            ),
+            /\s*/,
+            ')'
+        ),
+        sequence(
+            capture('.'),
+            capture(/-?[_A-Za-z][-\w]*/)
+        )
     )
-))
+)
 
@@ -44,0 +80,0 @@ console.log('selector / @global\n', selector)

src/at-rules.js

@@ -6,3 +6,3 @@ import {flatIter} from './helpers'
 /**
- * Hanldes at-rules
+ * Handles a single at-rules
  *
@@ -14,4 +14,8 @@ * @param {object} state - holds the localizer- and walker-related methods
  *                    if takes both parameters and a block.
- * @param {string} prefix - the current selector or the selector prefix
- *                          in case of nested rules
+ *                    k == [match, fullAtRule, atRuleType, params?]
+ *                    So in `@-webkit-keyframes foo`, we have
+ *                     - match = "@-webkit-keyframes foo"
+ *                     - fullAtRule = "@-webkit-keyframes"
+ *                     - atRuleType = "keyframes"
+ *                     - params = "foo"
  * @param {string|string[]|object|object[]} v - Either parameters for
@@ -21,11 +25,14 @@ *                                              block-less rules or
  *                                              for the others.
- * @param {string} inAtRule - are we nested in an at-rule?
+ * @param {string} prefix - the current selector or the selector prefix
+ *                          in case of nested rules
  * @param {boolean} local - are we in @local or in @global scope?
+ * @param {string} nestingDepth - are we nested in an at-rule or a selector?
  */
 
-export function atRules(state, emit, k, v, prefix, local, inAtRule) {
+export function atRules(state, emit, k, v, prefix, local, nestingDepth) {
 
-  for (var i = 0; i < state.$a.length; i++) {
+  // First iterate over user-provided at-rules and return if one of them corresponds to the current one
+  for (var i = 0; i < state.$atHandlers.length; i++) {
 
-    if (state.$a[i](state, emit, k, v, prefix, local, inAtRule)) return
+    if (state.$atHandlers[i](state, emit, k, v, prefix, local, nestingDepth)) return
 
@@ -35,3 +42,3 @@ }
   // using `/^global$/.test(k[2])` rather that 'global' == k[2] gzips
-  // slightly better because of the regexps test further down.
+  // slightly better thanks to the regexps tests further down.
   // It is slightly less efficient but this isn't a critical path.
@@ -41,3 +48,3 @@
 
-    rules(state, emit, prefix, v, 0, inAtRule)
+    rules(state, emit, prefix, v, 0, nestingDepth)
 
@@ -47,3 +54,3 @@
 
-    rules(state, emit, prefix, v, 1, inAtRule)
+    rules(state, emit, prefix, v, 1, nestingDepth)
 
@@ -53,5 +60,5 @@
 
-    if (!local || inAtRule) return emit.a('@-error-bad-at-adopt-placement' , JSON.stringify(k[0]), 0)
+    if (!local || nestingDepth) return emit.err('@adopt global or nested: ' + k[0])
 
-    if (!/^\.?[_A-Za-z][-\w]*$/.test(k[3])) return emit.a('@-error-bad-at-adopter', k[3], 0)
+    if (!/^\.?[_A-Za-z][-\w]*$/.test(k[3])) return emit.err('bad adopter ' + JSON.stringify(k[3]) + ' in ' + k[0])
 
@@ -61,3 +68,3 @@ i = []
 
-      if(!/^\.?[_A-Za-z][-\w]*(?:\s+\.?[_A-Za-z][-\w]*)*$/.test(asString = adoptee.toString())) emit.a('@-error-bad-at-adoptee', JSON.stringify(adoptee), 0)
+      if(adoptee == null || !/^\.?[_A-Za-z][-\w]*(?:\s+\.?[_A-Za-z][-\w]*)*$/.test(asString = adoptee + '')) emit.err('bad adoptee '+ JSON.stringify(adoptee) + ' in ' + k[0])
 
@@ -70,4 +77,4 @@ else i.push(asString.replace(/\./g, ''))
     if (i.length) {
-      state.l(k[3] = k[3].replace(/\./g, ''))
-      state.n[k[3]] += (' ' + i.join(' '))
+      state.localize(k[3] = k[3].replace(/\./g, ''))
+      state.names[k[3]] += (' ' + i.join(' '))
     }
@@ -79,3 +86,3 @@
 
-      emit.a(k[0], v)
+      emit.atrule(k[1], k[2], v)
 
@@ -88,7 +95,7 @@ })(v)
 
-      emit.a(k[1], '', 1)
+      emit.atrule(k[1], k[2], k[3], 1)
 
       declarations(state, emit, '', v, local)
 
-      emit.A(k[1], '')
+      emit._atrule()
 
@@ -103,3 +110,3 @@ })(v)
         /(var\([^)]+\))|:?global\(\s*([_A-Za-z][-\w]*)\s*\)|()(-?[_A-Za-z][-\w]*)/,
-        state.L
+        state.localizeReplacer
       )
@@ -109,3 +116,3 @@ }
 
-    emit.a(k[1], k[3], 1)
+    emit.atrule(k[1], k[2], k[3], 1)
 
@@ -121,3 +128,3 @@ if ('page' == k[2]) {
         'keyframes' == k[2] ? '' : prefix,
-        v, local, 1
+        v, local, nestingDepth + 1
       )
@@ -127,9 +134,9 @@
 
-    emit.A(k[1], k[3])
+    emit._atrule()
 
   } else {
 
-    emit.a('@-error-unsupported-at-rule', JSON.stringify(k[0]))
+    emit.err('Unsupported at-rule: ' + k[0])
 
   }
 }

src/declarations.js

@@ -65,3 +65,3 @@ import {own, type, ARRAY, OBJECT} from './helpers'
 
-        return o.replace(/(var\([^)]+\))|:?global\(\s*([_A-Za-z][-\w]*)\s*\)|()(-?[_A-Za-z][-\w]*)/, state.L)
+        return o.replace(/^\s*(?:(var\([^)]+\))|:?global\(\s*([_A-Za-z][-\w]*)\s*\)|()(-?[_A-Za-z][-\w]*))/, state.localizeReplacer)
 
@@ -71,5 +71,5 @@ }).join(',')
 
-    emit.d(k, o)
+    emit.decl(k, o)
 
   }
 }

src/helpers.js

@@ -13,3 +13,3 @@ var
 
-function Default(target, source) {
+function defaults(target, source) {
   for (var k in source) if (own.call(source, k)) {
@@ -40,2 +40,3 @@ if (k.indexOf('$') && !(k in target)) target[k] = source[k]
  * ignoring comas in strings, comments and in :pseudo-selectors(parameter, lists).
+ *
  * @param {string} selector
@@ -64,4 +65,3 @@ * @return {string[]}
 
-// This is like the `selectorTokenizer`, but for the `&` operator
-
+// Like the `selectorTokenizer`, but for the `&` operator
 var ampersandTokenizer = /&|"(?:\\.|[^"\n])*"|'(?:\\.|[^'\n])*'|\/\*[\s\S]*?\*\//g
@@ -81,2 +81,3 @@
   split.unshift(selector)
+  if (split.length === 1) split.unshift('')
   res = [split[0]]
@@ -98,3 +99,3 @@ for (o = 1; o < split.length; o++) {
   ARRAY, FUNCTION, OBJECT, STRING,
-  ampersand, cartesian, Default,
+  ampersand, cartesian, defaults,
   emptyArray, emptyObject,
@@ -101,0 +102,0 @@ flatIter, freeze, own,

src/main.js

@@ -1,2 +0,2 @@
-import {Default, emptyArray, emptyObject, flatIter, freeze, type, FUNCTION} from './helpers'
+import {defaults, emptyArray, emptyObject, flatIter, freeze, type, FUNCTION} from './helpers'
 import {closeSelectors, rules} from './rules'
@@ -10,28 +10,32 @@ import {declarations} from './declarations'
 
-  // palceholder for the buffer used by the `$sink` handlers
-  var buf
+  // the buffer that accumulates the output. Initialized in `$sink.i()`
+  var buf, err
 
   // the bottom of the 'codegen' stream. Mirrors the `$filter` plugin API.
   var $sink = {
-    // Init
-    i: function(){buf=[]},
-    // done (eXit)
-    x: function (raw) {return raw ? buf : buf.join('')},
-    // start At-rule
-    a: function (rule, argument, takesBlock) {
-      buf.push(rule, argument && ' ',argument, takesBlock ? ' {\n' : ';\n')
+    init: function(){buf=[], err=[]},
+    done: function (raw) {
+      if (err.length != 0) throw new Error('j2c error(s): ' + JSON.stringify(err,null,2) + 'in context:\n' + buf.join(''))
+      return raw ? buf : buf.join('')
     },
-    // end At-rule
-    A: function ()            {buf.push('}\n')},
-    // start Selector
-    s: function (selector)    {buf.push(selector, ' {\n')},
-    // end Selector
-    S: function ()            {buf.push('}\n')},
-    // declarations
-    d: function (prop, value) {buf.push(prop, prop && ':', value, ';\n')}
+    err: function(msg) {
+      err.push(msg)
+      buf.push('/* +++ ERROR +++ ' + msg + ' */\n')
+    },
+    atrule: function (rule, kind, param, takesBlock) {
+      buf.push(rule, param && ' ', param, takesBlock ? ' {' : ';', _instance.endline)
+    },
+    // close atrule
+    _atrule: function () {buf.push('}', _instance.endline)},
+    rule: function (selector) {buf.push(selector, ' {', _instance.endline)},
+    // close rule
+    _rule: function () {buf.push('}', _instance.endline)},
+    decl: function (prop, value) {buf.push(prop, prop && ':', value, ';', _instance.endline)}
   }
 
+  // holds the `$filter` and `$at` handlers
   var $filters = [closeSelectors]
   var $atHandlers = []
 
+  // the public API (see the main docs)
   var _instance = {
@@ -42,3 +46,5 @@ at: at,
     names: {},
+    endline: '\n',
     suffix: '__j2c-' +
+      // 128 bits of randomness
       Math.floor(Math.random() * 0x100000000).toString(36) + '-' +
@@ -48,13 +54,32 @@ Math.floor(Math.random() * 0x100000000).toString(36) + '-' +
       Math.floor(Math.random() * 0x100000000).toString(36),
-    use: function() {
-      _use(emptyArray.slice.call(arguments))
-      return _instance
+    $plugins: [],
+    sheet: function(tree) {
+      var emit = _createOrRetrieveStream(0)
+      emit.init()
+      rules(
+        _walkers[0],
+        emit,
+        '', // prefix
+        tree,
+        1,  // local, by default
+        0   // nesting depth
+      )
+
+      return emit.done()
     },
-    $plugins: []
+    inline: function (tree, options) {
+      var emit = _createOrRetrieveStream(1)
+      emit.init()
+      declarations(
+        _walkers[1],
+        emit,
+        '', // prefix
+        tree,
+        !(options && options.global)   // local, by default
+      )
+      return emit.done()
+    }
   }
 
-  var _streams = []
-
-  // The `state` (for the core) / `walker` (for the plugins) tables.
-
+  // The `state` (for the core functions) / `walker` (for the plugins) tables.
   var _walkers = [
@@ -64,17 +89,17 @@ // for j2c.sheet
       // helpers for locaizing class and animation names
-      L: _localizeReplacer, // second argument to String.prototype.replace
-      l: _localize,         // mangles local names
-      n: _instance.names,    // local => mangled mapping
-      $a: $atHandlers,      // extra at-rules
+      localizeReplacer: _localizeReplacer, // second argument to String.prototype.replace
+      localize: _localize,                 // mangles local names
+      names: _instance.names,              // local => mangled mapping
+      $atHandlers: $atHandlers,            // extra at-rules
       // The core walker methods, to be provided to plugins
-      a: atRules,
-      d: declarations,
-      r: rules
+      atrule: atRules,
+      decl: declarations,
+      rule: rules
     },
     // likewise, for j2c.inline (idem with `$a`, `a` and `s` removed)
     {
-      L: _localizeReplacer,
-      l: _localize,
-      n: _instance.names,
-      d: declarations
+      localizeReplacer: _localizeReplacer,
+      localize: _localize,
+      names: _instance.names,
+      decl: declarations
     }
@@ -84,32 +109,2 @@ ]
 
-  // The main API functions
-
-  _instance.sheet = function(tree) {
-    var emit = _getStream(0)
-    emit.i()
-    rules(
-      _walkers[0],
-      emit,
-      '',    // prefix
-      tree,
-      1,      // local, by default
-      0     // inAtRule
-    )
-
-    return emit.x()
-  }
-
-  _instance.inline = function (tree) {
-    var emit = _getStream(1)
-    emit.i()
-    declarations(
-      _walkers[1],
-      emit,
-      '',         // prefix
-      tree,
-      1           //local
-    )
-    return emit.x()
-  }
-
   // inner helpers
@@ -138,3 +133,3 @@
 
-    Default(_instance.names, plugin.$names || emptyObject)
+    defaults(_instance.names, plugin.$names || emptyObject)
 
@@ -145,21 +140,37 @@ _use(plugin.$plugins || emptyArray)
 
-    Default(_instance, plugin)
+    defaults(_instance, plugin)
   })
 
-  function _getStream(inline) {
+
+  var _streams = []
+  /**
+   * returns the codegen streams, creating them if necessary
+   * @param
+   */
+  function _createOrRetrieveStream(inline) {
+    // build the stream processors if needed
     if (!_streams.length) {
-      for(var i = 0; i < 2; i++){
-        $filters[$filters.length - i] = function(_, inline) {return inline ? {i:$sink.i, d:$sink.d, x:$sink.x} : $sink}
+      // append the $sink as the ultimate filter
+      $filters.push(function(_, inline) {return inline ? {init:$sink.init, decl:$sink.decl, done:$sink.done, err: $sink.err} : $sink})
+      for(var i = 0; i < 2; i++){ // 0 for j2c.sheet, 1 for j2c.inline
         for (var j = $filters.length; j--;) {
-          _streams[i] = freeze(Default(
-            $filters[j](_streams[i], !!i, _walkers[i]),
-            _streams[i]
-          ))
+          _streams[i] = freeze(
+            defaults(
+              $filters[j](_streams[i], !!i),
+              _streams[i]
+            )
+          )
         }
       }
     }
-    var res = _streams[inline]
-    return res
+    return _streams[inline]
   }
 
+  /**
+   * Returns a localized version of a given name.
+   * Registers the pair in `instnace.name` if needed.
+   *
+   * @param {string} name - the name to localize
+   * @return {string} - the localized version
+   */
   function _localize(name) {
@@ -170,11 +181,19 @@ if (!_instance.names[name]) _instance.names[name] = name + _instance.suffix
 
-  function _localizeReplacer(match, string, global, dot, name) {
-    if (string || global) return string || global
-    return dot + _localize(name)
+  /**
+   * Used as second argument for str.replace(localizeRegex, replacer)
+   * `ignore`, `global` and `(dot, name)` are mutually exclusive
+   *
+   * @param {string} match - the whole match (ignored)
+   * @param {string|null} ignore - a comment or a string literal
+   * @param {string|null} global - a global name
+   * @param {string|null} dot - either '.' for a local class name or the empty string otherwise
+   * @param {string|null} name - the name to localize
+   * @return {string}
+   */
+  function _localizeReplacer(match, ignore, global, dot, name) {
+    return ignore || global || dot + _localize(name)
   }
 
+  _use(emptyArray.slice.call(arguments))
   return _instance
 }
-
-var _j2c = j2c()
-'sheet|inline|names|at|global|kv|suffix'.split('|').map(function(m){j2c[m] = _j2c[m]})

src/rules.js

@@ -13,6 +13,6 @@ import {type, ARRAY, OBJECT, STRING, ampersand, own, splitSelector} from './helpers'
  * @param {array|string|object} tree - a source object or sub-object.
- * @param {string} inAtRule - are we nested in an at-rule?
+ * @param {string} nestingDepth - are we nested in an at-rule?
  * @param {boolean} local - are we in @local or in @global scope?
  */
-export function rules(state, emit, prefix, tree, local, inAtRule) {
+export function rules(state, emit, prefix, tree, local, nestingDepth) {
   var k, v, inDeclaration, kk
@@ -30,3 +30,3 @@
 
-          emit.s(prefix)
+          emit.rule(prefix)
 
@@ -52,3 +52,3 @@ }
           /^(.(?:-[\w]+-)?([_A-Za-z][-\w]*))\b\s*(.*?)\s*$/.exec(k) || [k,'@','',''],
-          v, prefix, local, inAtRule
+          v, prefix, local, nestingDepth
         )
@@ -62,7 +62,7 @@
           state, emit,
-          // `prefix` ... Hefty. Ugly. Sadly necessary.
-          //
-          (prefix.length > 0 && (/,/.test(prefix) || /,/.test(k))) ?
+          // build the selector `prefix` for the next iteration.
+          // ugly and full of redundant bits but so far the fastest/shortest.gz
+          /*0 if*/(prefix.length > 0 && (/,/.test(prefix) || /,/.test(k))) ?
 
-            /*0*/ (kk = splitSelector(prefix), splitSelector(
+            /*0 then*/ (kk = splitSelector(prefix), splitSelector(
               local ?
@@ -72,3 +72,3 @@
                   /("(?:\\.|[^"\n])*"|'(?:\\.|[^'\n])*'|\/\*[\s\S]*?\*\/)|:global\(\s*(\.-?[_A-Za-z][-\w]*)\s*\)|(\.)(-?[_A-Za-z][-\w]*)/g,
-                  state.L
+                  state.localizeReplacer
                 ) :
@@ -83,5 +83,5 @@
 
-            /*0*/ /&/.test(k) ?
+            /*0 else*/ /*1 if*/ /&/.test(k) ?
 
-              /*1*/ ampersand(
+              /*1 then*/ ampersand(
                 local ?
@@ -91,3 +91,3 @@
                     /("(?:\\.|[^"\n])*"|'(?:\\.|[^'\n])*'|\/\*[\s\S]*?\*\/)|:global\(\s*(\.-?[_A-Za-z][-\w]*)\s*\)|(\.)(-?[_A-Za-z][-\w]*)/g,
-                    state.L
+                    state.localizeReplacer
                   ) :
@@ -99,3 +99,3 @@
 
-              /*1*/ prefix + (
+              /*1 else*/ prefix + (
                 local ?
@@ -105,3 +105,3 @@
                     /("(?:\\.|[^"\n])*"|'(?:\\.|[^'\n])*'|\/\*[\s\S]*?\*\/)|:global\(\s*(\.-?[_A-Za-z][-\w]*)\s*\)|(\.)(-?[_A-Za-z][-\w]*)/g,
-                    state.L
+                    state.localizeReplacer
                   ) :
@@ -111,3 +111,3 @@
                 ),
-           v, local, inAtRule
+           v, local, nestingDepth + 1
         )
@@ -123,3 +123,3 @@
 
-      rules(state, emit, prefix, tree[k], local, inAtRule)
+      rules(state, emit, prefix, tree[k], local, nestingDepth)
 
@@ -131,5 +131,5 @@ }
     // CSS hacks or ouptut of `j2c.inline`.
+    if (!prefix.length) emit.err('No selector')
+    emit.rule(prefix || ' ')
 
-    emit.s(prefix.length > 0 ? prefix : ':-error-no-selector')
-
     declarations(state, emit, '', tree, local)
@@ -147,3 +147,3 @@
 // contains arrays.
-// There's no `S` handler, because the core compiler never
+// There's no `_rule` handler, because the core compiler never
 // calls it.
@@ -153,24 +153,23 @@ export function closeSelectors(next, inline) {
   return inline ? next : {
-    i: function(){lastSelector = 0; next.i()},
-    x: function (raw) {
-      if (lastSelector) {next.S(); lastSelector = 0}
-      return next.x(raw)
+    init: function(){lastSelector = 0; next.init()},
+    done: function (raw) {
+      if (lastSelector) {next._rule(); lastSelector = 0}
+      return next.done(raw)
     },
-    a: function (rule, param, takesBlock) {
-      if (lastSelector) {next.S(); lastSelector = 0}
-      next.a(rule, param, takesBlock)
+    atrule: function (rule, kind, param, takesBlock) {
+      if (lastSelector) {next._rule(); lastSelector = 0}
+      next.atrule(rule, kind, param, takesBlock)
     },
-    A: function (rule) {
-      if (lastSelector) {next.S(); lastSelector = 0}
-      next.A(rule)
+    _atrule: function (rule) {
+      if (lastSelector) {next._rule(); lastSelector = 0}
+      next._atrule(rule)
     },
-    s: function (selector) {
+    rule: function (selector) {
       if (selector !== lastSelector){
-        if (lastSelector) next.S()
-        next.s(selector)
+        if (lastSelector) next._rule()
+        next.rule(selector)
         lastSelector = selector
       }
-    },
-    d: next.d
+    }
   }
 }

New alerts

License Policy Violation

License

This package is not allowed per your license policy. Review the package's license to ensure compliance.

Found 1 instance in 1 package

Major refactor

Supply chain risk

Package has recently undergone a major refactor. It may be unstable or indicate significant internal changes. Use caution when updating to versions that include significant changes.

Found 1 instance in 1 package

Fixed alerts

License Policy Violation

License

This package is not allowed per your license policy. Review the package's license to ensure compliance.

Found 1 instance in 1 package

Improved metrics

Total package byte prevSize

992685

increased by370.09%

Dev dependency count

16

decreased by-5.88%

Number of package files

139

increased by275.68%

Lines of code

14926

increased by247.04%

Number of lines in readme file

712

increased by0.14%

Worsened metrics

Number of low supply chain risk alerts

5

increased by66.67%

Number of medium supply chain risk alerts

1

increased byInfinity%

No dependency changes