regular-grammar - npm Package Compare versions

Comparing version 0.0.5 to 0.1.0

package.json

 {
     "name": "regular-grammar",
-    "version": "0.0.5",
+    "version": "0.1.0",
     "description": "A simple regular grammar/parser generator",
@@ -5,0 +5,0 @@ "author": "Victor Grishchenko <[e-mail]>",

print.js

 "use strict";
 
-const grammar = require('.');
+let IM ='abcdefgh';
+for(let i=0; i<20; i++)
+    IM = IM+IM;
 
-for(let key in grammar._parsers)
-    console.log(key+" parser is", grammar._parsers[key]);
+const re = /abcdefgh/g;
+//let c = 0, m;
+//while ( m=re.exec(IM) )
+//    c++;
+
+const m = IM.match(re);
+
+console.log(m.length);

src/Grammar.js

@@ -8,2 +8,3 @@ /** The class generates regex _parsers for simple regular languages
         this._rules = rules;
+        this._rules.EMPTY = new RegExp();
         // {RULE: regex_str}
@@ -17,2 +18,3 @@ this._parsers = Object.create(null);
         }
+        this._patterns.EMPTY = '';
         this._splitters = Object.create(null);
@@ -28,3 +30,3 @@ }
         const m = splitter.exec(text);
-        return m && m[0].length === text.length;
+        return m !== null && m[0].length === text.length;
     }
@@ -45,8 +47,17 @@
         while (m = Grammar.TRIPLET_RE.exec(rule)) {
+            if (m[0].length === 0) {
+                Grammar.TRIPLET_RE.lastIndex = m.index + 1;
+                continue;
+            }
+            const formula = m[0];
+            const marker = m[2] ? m[2] : (m[1] || '');
+            const rule = m[3] || 'EMPTY';
+            const quantifier = m[4] || '';
+            const repeating = m[4] !== undefined && (m[4] === '*' || m[4] === '+' || m[4][0] === '{');
             const triplet = {
-                formula: m[0],
-                marker: m[1] || '',
-                rule: m[2],
-                quantifier: m[3] || '',
-                repeating: m[3] === '*' || m[3] === '+',
+                formula,
+                marker,
+                rule,
+                quantifier,
+                repeating,
             };
@@ -79,24 +90,51 @@ ret.push(triplet);
 
+    triplet_re (t) {
+        let ret = sterilize(this.pattern(t.rule));
+        const q = t.quantifier === '?' ? '?' : '';
+        let m = t.marker;
+        if (m.length === 1) {
+            m = '\\' + m;
+        }
+        if (!t.repeating) {
+            if (t.marker.length > 1) {
+                ret = '(' + m + '\\s*' + ret + ')' + q;
+            } else if (q === '?') {
+                ret = '(?:' + (m ? m + '\\s*' : '') + '(' + ret + '))' + q;
+            } else {
+                ret = m + '(' + ret + ')';
+            }
+        } else {
+            ret = '((?:' + m + '\\s*' + ret + '\\s*)' + t.quantifier + ')';
+        }
+        return ret;
+    }
+
+
     pattern (rule_name) {
         if (rule_name in this._patterns) { return this._patterns[rule_name]; }
         const triplets = this.triplets(rule_name);
-        const is_chain = triplets.every(t => t.quantifier !== '|');
-        const pattern = triplets.map((t) => {
-            let ret = sterilize(this.pattern(t.rule));
-            if (t.marker.length > 1) {
-                ret = t.marker + ret;
+        // detect chains, strip |, make regex
+        let joined = '';
+        let chain = true;
+        triplets.forEach((t) => {
+            const p = this.triplet_re(t);
+            if (chain) {
+                if (t.quantifier === '|') {
+                    joined += '(?:';
+                    chain = false;
+                } else {
+                    if (joined) {
+                        joined += '\\s*';
+                    }
+                }
+                joined += p;
+            } else {
+                joined += '|' + p;
+                if (t.quantifier !== '|') {
+                    joined += ')';
+                    chain = true;
+                }
             }
-            if (!t.repeating) { ret = '(' + ret + ')'; }
-            if (t.marker.length === 1) {
-                ret = '\\' + t.marker + ret;
-            }
-            if (t.quantifier && t.quantifier !== '|') {
-                ret = '(?:' + ret + ')' + t.quantifier;
-            }
-            if (t.repeating) {
-                ret = '(' + ret + ')';
-            }
-            return ret;
         });
-        this._patterns[rule_name] = pattern.join(is_chain ? '\\s*' : '|');
+        this._patterns[rule_name] = joined;
 
@@ -143,3 +181,3 @@ return this._patterns[rule_name];
 
-Grammar.TRIPLET_RE = /(\[.*?\]|[^A-Za-z0-9\s]?)([A-Z][A-Z0-9_]+)([*+?|]?)/g;
+Grammar.TRIPLET_RE = /(\[.*?\]|"([^"]+)"|[^A-Za-z0-9\s])?([A-Z][A-Z0-9_]*)?([*+?|]|{\d+(?:,\d+)?})?/g;
 
@@ -146,0 +184,0 @@ function sterilize (pattern) {

test/01_grammar.js

 const tap = require('tape');
 const Grammar = require('..');
 
-const SWARM_GRAMMAR_RULES = {
+const SWARM_GRAMMAR_RULES = { // swarm 1.9.99 grammar :)
 
@@ -14,3 +14,3 @@ NUMBER: /\d+(\.\d+([eE]-?\d+)?)?/,
     SPEC: 'ID? .ID? @ID? :ID?',
-    CONSTANT: 'NUMBER| STRING| >ID| EMPTY|',
+    CONSTANT: 'NUMBER| STRING| >ID| EMPTY',
 
@@ -66,3 +66,3 @@ RUN: 'INT /BASE? [+%-]INT?',
     tap.ok(grammar.is('  0\n+0 ', 'ID'));
-    tap.notOk(grammar.is('0+ 0', 'ID'));
+    tap.ok(grammar.is('0+ 0', 'ID'));
     // tap.ok( grammar.is('{a:1, b: "two " }', 'MAP'), 'the MAP type' );
@@ -122,3 +122,3 @@
 tap('grammar.01.E benchmark', (tap) => {
-    const event_str = '#object+author.json@sometime+origin:field="value"';
+    const event_str = '#object+author.json@sometime+origin:field="value"\n';
     let mln_str = '';
@@ -125,0 +125,0 @@ const ev_count = 100000;

New alerts

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License

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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

42654

increased by8.36%

Number of package files

17

increased by6.25%

Lines of code

352

increased by40.8%

No dependency changes