the definitive JavaScript type testing library. 

the definitive JavaScript type testing library

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enricomarino

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  * Version bump to resolve npm bug with v3.0.0

  * is.empty should return true for falsy values ([#13](https://github.com/enricomarino/is/issues/13), [#14](https://github.com/enricomarino/is/issues/14))

  * All grade A-supported `node`/`iojs` versions now ship with an `npm` that understands `^`.

  * Test on `iojs` `v1.2` and `v1.3`, `node` `v0.12`; speed up builds; allow failures on all but two latest minor versions.

  * `toString` breaks in some browsers; using `toStr` instead.

  * Add `is.hex` and `is.base64` [#12](https://github.com/enricomarino/is/issues/12)

  * Lock `covert` to v1.0.0 [substack/covert#9](https://github.com/substack/covert/issues/9)

  * `undefined` can be redefined in ES3 browsers.

  * Update `jscs.json` and make style consistent

  * Add a non-deprecated method for is.null

  * Use a more reliable valueOf coercion for is.false/is.true

  * Running `npm run lint` as part of tests.

  * is.arguments -> is.args, because reserved words.

  * "undefined" is a reserved word in ES3 browsers.

  * Optimizing is.equal to return early if value and other are strictly equal.

  * is.decimal(Infinity) shouldn't be true [#11](https://github.com/enricomarino/is/issues/11)

  * Fix lots of tests [#9](https://github.com/enricomarino/is/issues/9)

  * Update tape [#8](https://github.com/enricomarino/is/issues/8)

  * Use `tap` instead of `tape` [#7](https://github.com/enricomarino/is/issues/7)

 * the definitive JavaScript type testing library

  symbolValueOf = Symbol.prototype.valueOf;

var base64Regex = /^([A-Za-z0-9+/]{4})*([A-Za-z0-9+/]{4}|[A-Za-z0-9+/]{3}=|[A-Za-z0-9+/]{2}==)$/;

 * @return {Boolean} true if `value` is a type of `type`, false otherwise

is.a = is.type = function (value, type) {

 * @return {Boolean} true if 'value' is defined, false otherwise

 * @return {Boolean} true if `value` is empty, false otherwise

  if ('[object Array]' === type || '[object Arguments]' === type || '[object String]' === type) {

      if (owns.call(value, key)) { return false; }

 * @param {Mixed} other value to compare with

 * @return {Boolean} true if `value` is equal to `other`, false otherwise

      if (!is.equal(value[key], other[key]) || !(key in other)) {

      if (!is.equal(value[key], other[key]) || !(key in value)) {

      if (!is.equal(value[key], other[key])) {

    return value.prototype === other.prototype;

    return value.getTime() === other.getTime();

 * @return {Boolean} true if `value` is hosted by `host`, false otherwise

  return type === 'object' ? !!host[value] : !NON_HOST_TYPES[type];

 * Test if `value` is an instance of `constructor`.

 * @return {Boolean} true if `value` is an instance of `constructor`

is.instance = is['instanceof'] = function (value, constructor) {

 * @return {Boolean} true if `value` is null, false otherwise

    "test": "npm run lint && node test/index.js",

    "coverage-quiet": "covert test/index.js --quiet",

  "description": "the definitive JavaScript type testing library",

  "homepage": "https://github.com/enricomarino/is",

    "url": "git://github.com/enricomarino/is.git"

    t.ok(is.type(boolean, 'boolean'), '"' + boolean + '" is a boolean');

  var numbers = [1, 0 / 1, 0 / -1, NaN, Infinity, -Infinity];

    t.ok(is.type(number, 'number'), '"' + number + '" is a number');

    t.ok(is.type(object, 'object'), '"' + object + '" is an object');

    t.ok(is.type(string, 'string'), '"' + string + '" is a string');

  t.ok(is.type(undefined, 'undefined'), 'undefined is undefined');

  t.ok(is.undef(), 'absent undefined is undefined');

  t.ok(is.undef(undefined), 'literal undefined is undefined');

  t.notOk(is.undef(null), 'null is not undefined');

  t.notOk(is.undef({}), 'object is not undefined');

  t.notOk(is.defined(), 'undefined is not defined');

  t.ok(is.defined(null), 'null is defined');

  t.ok(is.defined({}), 'object is undefined');

  t.ok(is.empty(''), 'empty string is empty');

  t.ok(is.empty(new String()), 'empty String object is empty');

  t.ok(is.empty([]), 'empty array is empty');

  t.ok(is.empty({}), 'empty object is empty');

  t.ok(is.empty(), 'undefined is empty');

  t.ok(is.empty(undefined), 'undefined is empty');

  t.ok(is.empty(false), 'false is empty');

  (function () { t.ok(is.empty(arguments), 'empty arguments is empty'); }());

  t.notOk(is.empty({ a: 1 }), 'nonempty object is not empty');

  t.notOk(is.empty(true), 'true is not empty');

  t.notOk(is.empty(false), 'false is not empty');

  t.notOk(is.empty(/a/g), 'regex is not empty');

  t.notOk(is.empty(new Date()), 'date is not empty');

    var primitives = [true, false, undefined, null, '', 'foo', 0, Infinity, -Infinity];

    for (var i = 0; i < primitives.length; ++i) {

      pt.ok(is.equal(primitives[i], primitives[i]), 'primitives are equal to themselves: ' + primitives[i]);

    at.ok(is.equal([1, 2, 3], [1, 2, 3]), 'arrays are shallowly equal');

    at.ok(is.equal([1, 2, [3, 4]], [1, 2, [3, 4]]), 'arrays are deep equal');

    at.notOk(is.equal([1, 2], [2, 3]), 'inequal arrays are not equal');

    at.notOk(is.equal([1, 2, 3], [2, 3]), 'inequal length arrays are not equal');

    at.ok(is.equal(arr, arr), 'array is equal to itself');

    dt.ok(is.equal(now, new Date(now.getTime())), 'two equal date objects are equal');

      dt.notOk(is.equal(now, new Date()), 'two inequal date objects are not equal');

  t.test('plain objects', function (ot) {

    ot.ok(is.equal({ a: 1, b: 2, c: 3 }, { a: 1, b: 2, c: 3 }), 'objects are shallowly equal');

    ot.ok(is.equal({ a: { b: 1 } }, { a: { b: 1 } }), 'objects are deep equal');

    ot.notOk(is.equal({ a: 1 }, { a: 2 }), 'inequal objects are not equal');

  t.test('object instances', function (ot) {

    ot.ok(is.equal(f, f), 'the same object instances are equal');

    ot.ok(is.equal(f, new F()), 'two object instances are equal when the prototype and props are the same');

    ot.ok(is.equal(f, new G()), 'two object instances are equal when the prototype is not the same, but props are');

    ot.notOk(is.equal(f, g), 'object instances are not equal when the prototype and props are not the same');

    ot.notOk(is.equal(g, f), 'object instances are not equal when the prototype and props are not the same');

    ft.notEqual(F.prototype, G.prototype, 'F and G have different prototypes');

		@@ -0,1 +1,12 @@
		3.0.1 / 2015-02-22
		==================
		* Version bump to resolve npm bug with v3.0.0

		3.0.0 / 2015-02-21
		==================
		* is.empty should return true for falsy values ([#13](https://github.com/enricomarino/is/issues/13), [#14](https://github.com/enricomarino/is/issues/14))
		* All grade A-supported `node`/`iojs` versions now ship with an `npm` that understands `^`.
		* Test on `iojs` `v1.2` and `v1.3`, `node` `v0.12`; speed up builds; allow failures on all but two latest minor versions.
		* Update `jscs`

		2.2.1 / 2015-02-06
		@@ -2,0 +13,0 @@ ==================

		@@ -91,3 +91,3 @@

		return false;
		return !value;
		};
		@@ -764,2 +764,1 @@
		};

		{
		"name": "is",
		"version": "2.2.1",
		"version": "3.0.1",
		"main": "index.js",
		@@ -35,6 +35,6 @@ "scripts": {
		"devDependencies": {
		"tape": "~3.5.0",
		"foreach": "~2.0.5",
		"covert": "1.0.0",
		"jscs": "~1.10.0"
		"tape": "^3.5.0",
		"foreach": "^2.0.5",
		"covert": "^1.0.1",
		"jscs": "^1.11.3"
		},
		@@ -41,0 +41,0 @@ "testling": {

		@@ -53,6 +53,11 @@ var test = require('tape');
		t.ok(is.empty({}), 'empty object is empty');
		t.ok(is.empty(null), 'null is empty');
		t.ok(is.empty(), 'undefined is empty');
		t.ok(is.empty(undefined), 'undefined is empty');
		t.ok(is.empty(false), 'false is empty');
		t.ok(is.empty(0), '0 is empty');
		t.ok(is.empty(NaN), 'nan is empty');
		(function () { t.ok(is.empty(arguments), 'empty arguments is empty'); }());
		t.notOk(is.empty({ a: 1 }), 'nonempty object is not empty');
		t.notOk(is.empty(true), 'true is not empty');
		t.notOk(is.empty(false), 'false is not empty');
		t.notOk(is.empty(/a/g), 'regex is not empty');
		@@ -92,3 +97,3 @@ t.notOk(is.empty(new Date()), 'date is not empty');
		dt.end();
		}, 1);
		}, 10);
		});
		@@ -620,2 +625,1 @@
		});

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