Shims for upcoming ES6 standard and other goodies implemented strictly with ECMAScript conventions in mind.
It's designed to be used in compliant ECMAScript 5 or ECMAScript 6 environments. Older environments are not supported, although most of the features should work with correct ECMAScript 5 shim on board.
When used in ECMAScript 6 environment, native implementation (if valid) takes precedence over shims.
To port it to Browser or any other (non CJS) environment, use your favorite CJS bundler. No favorite yet? Try: [Browserify](http://browserify.org/), [Webmake](https://github.com/medikoo/modules-webmake) or [Webpack](http://webpack.github.io/)
### Usage
#### ECMAScript 6 features
You can force ES6 features to be implemented in your environment, e.g. following will assign `from` function to `Array` (only if it's not implemented already).
```javascript
require("es5-ext/array/from/implement");
Array.from("foo"); // ['f', 'o', 'o']
```
You can also access shims directly, without fixing native objects. Following will return native `Array.from` if it's available and fallback to shim if it's not.
```javascript
var aFrom = require("es5-ext/array/from");
aFrom("foo"); // ['f', 'o', 'o']
```
If you want to use shim unconditionally (even if native implementation exists) do:
```javascript
var aFrom = require("es5-ext/array/from/shim");
aFrom("foo"); // ['f', 'o', 'o']
```
##### List of ES6 shims
It's about properties introduced with ES6 and those that have been updated in new spec.
-`RegExp.prototype.sticky` -> Implement with `require('es5-ext/reg-exp/#/sticky/implement')`, use as function with `require('es5-ext/reg-exp/#/is-sticky')`
-`RegExp.prototype.unicode` -> Implement with `require('es5-ext/reg-exp/#/unicode/implement')`, use as function with `require('es5-ext/reg-exp/#/is-unicode')`
**es5-ext** provides also other utils, and implements them as if they were proposed for a standard. It mostly offers methods (not functions) which can directly be assigned to native prototypes:
See [es5-extend](https://github.com/wookieb/es5-extend#es5-extend), a great utility that automatically will extend natives for you.
**Important:** Remember to **not** extend natives in scope of generic reusable packages (e.g. ones you intend to publish to npm). Extending natives is fine **only** if you're the _owner_ of the global scope, so e.g. in final project you lead development of.
When you're in situation when native extensions are not good idea, then you should use methods indirectly:
```javascript
var flatten = require("es5-ext/array/#/flatten");
flatten.call([1, [2, [3, 4]]]); // [1, 2, 3, 4]
```
for better convenience you can turn methods into functions:
```javascript
var call = Function.prototype.call;
var flatten = call.bind(require("es5-ext/array/#/flatten"));
flatten([1, [2, [3, 4]]]); // [1, 2, 3, 4]
```
You can configure custom toolkit (like [underscorejs](http://underscorejs.org/)), and use it throughout your application
_egal_ version of `indexOf` method. [_SameValueZero_](http://people.mozilla.org/~jorendorff/es6-draft.html#sec-samevaluezero) logic is used for comparision
_egal_ version of `lastIndexOf` method. [_SameValueZero_](http://people.mozilla.org/~jorendorff/es6-draft.html#sec-samevaluezero) logic is used for comparision
#### arr.entries() _(es5-ext/array/#/entries)_
[_Introduced with ECMAScript 6_](http://people.mozilla.org/~jorendorff/es6-draft.html#sec-array.prototype.entries).
Returns iterator object, which traverses the array. Each value is represented with an array, where first value is an index and second is corresponding to index value.
Invoking the function returned by this function only _n_ arguments are passed to the underlying function. If the underlying function is not saturated, the result is a function that passes all its arguments to the underlying function.
If _n_ is not provided then it defaults to context function length
Returns a function that when called will behave like context function called with initially passed arguments. If more arguments are suplilied, they are appended to initial args.
Serializes function into two (arguments and body) string tokens. Result is plain object with `args` and `body` properties.
### Math extensions
#### acosh(x) _(es5-ext/math/acosh)_
[_Introduced with ECMAScript 6_](http://people.mozilla.org/~jorendorff/es6-draft.html#sec-math.acosh).
#### asinh(x) _(es5-ext/math/asinh)_
[_Introduced with ECMAScript 6_](http://people.mozilla.org/~jorendorff/es6-draft.html#sec-math.asinh).
#### atanh(x) _(es5-ext/math/atanh)_
[_Introduced with ECMAScript 6_](http://people.mozilla.org/~jorendorff/es6-draft.html#sec-math.atanh).
#### cbrt(x) _(es5-ext/math/cbrt)_
[_Introduced with ECMAScript 6_](http://people.mozilla.org/~jorendorff/es6-draft.html#sec-math.cbrt).
#### clz32(x) _(es5-ext/math/clz32)_
[_Introduced with ECMAScript 6_](http://people.mozilla.org/~jorendorff/es6-draft.html#sec-math.clz32).
#### cosh(x) _(es5-ext/math/cosh)_
[_Introduced with ECMAScript 6_](http://people.mozilla.org/~jorendorff/es6-draft.html#sec-math.cosh).
#### expm1(x) _(es5-ext/math/expm1)_
[_Introduced with ECMAScript 6_](http://people.mozilla.org/~jorendorff/es6-draft.html#sec-math.expm1).
#### fround(x) _(es5-ext/math/fround)_
[_Introduced with ECMAScript 6_](http://people.mozilla.org/~jorendorff/es6-draft.html#sec-math.fround).
#### hypot([…values]) _(es5-ext/math/hypot)_
[_Introduced with ECMAScript 6_](http://people.mozilla.org/~jorendorff/es6-draft.html#sec-math.hypot).
#### imul(x, y) _(es5-ext/math/imul)_
[_Introduced with ECMAScript 6_](http://people.mozilla.org/~jorendorff/es6-draft.html#sec-math.imul).
#### log1p(x) _(es5-ext/math/log1p)_
[_Introduced with ECMAScript 6_](http://people.mozilla.org/~jorendorff/es6-draft.html#sec-math.log1p).
#### log2(x) _(es5-ext/math/log2)_
[_Introduced with ECMAScript 6_](http://people.mozilla.org/~jorendorff/es6-draft.html#sec-math.log2).
#### log10(x) _(es5-ext/math/log10)_
[_Introduced with ECMAScript 6_](http://people.mozilla.org/~jorendorff/es6-draft.html#sec-math.log10).
#### sign(x) _(es5-ext/math/sign)_
[_Introduced with ECMAScript 6_](http://people.mozilla.org/~jorendorff/es6-draft.html#sec-math.sign).
#### sinh(x) _(es5-ext/math/sinh)_
[_Introduced with ECMAScript 6_](http://people.mozilla.org/~jorendorff/es6-draft.html#sec-math.sinh).
#### tanh(x) _(es5-ext/math/tanh)_
[_Introduced with ECMAScript 6_](http://people.mozilla.org/~jorendorff/es6-draft.html#sec-math.tanh).
#### trunc(x) _(es5-ext/math/trunc)_
[_Introduced with ECMAScript 6_](http://people.mozilla.org/~jorendorff/es6-draft.html#sec-math.trunc).
### Number Constructor extensions
#### EPSILON _(es5-ext/number/epsilon)_
[_Introduced with ECMAScript 6_](http://people.mozilla.org/~jorendorff/es6-draft.html#sec-number.epsilon).
The difference between 1 and the smallest value greater than 1 that is representable as a Number value, which is approximately 2.2204460492503130808472633361816 x 10-16.
#### isFinite(x) _(es5-ext/number/is-finite)_
[_Introduced with ECMAScript 6_](http://people.mozilla.org/~jorendorff/es6-draft.html#sec-number.isfinite).
Whether value is finite. Differs from global isNaN that it doesn't do type coercion.
#### isInteger(x) _(es5-ext/number/is-integer)_
[_Introduced with ECMAScript 6_](http://people.mozilla.org/~jorendorff/es6-draft.html#sec-number.isinteger).
Whether value is integer.
#### isNaN(x) _(es5-ext/number/is-nan)_
[_Introduced with ECMAScript 6_](http://people.mozilla.org/~jorendorff/es6-draft.html#sec-number.isnan).
Whether value is NaN. Differs from global isNaN that it doesn't do type coercion.
`Object.create` alternative that provides workaround for [V8 issue](http://code.google.com/p/v8/issues/detail?id=2804).
When `null` is provided as a prototype, it's substituted with specially prepared object that derives from Object.prototype but has all Object.prototype properties shadowed with undefined.
It's quirky solution that allows us to have plain objects with no truthy properties but with turnable prototype.
Use only for objects that you plan to switch prototypes of and be aware of limitations of this workaround.
#### eq(x, y) _(es5-ext/object/eq)_
Whether two values are equal, using [_SameValueZero_](http://people.mozilla.org/~jorendorff/es6-draft.html#sec-samevaluezero) algorithm.
Analogous to Array.prototype.every. Returns true if every key-value pair in this object satisfies the provided testing function.
Optionally _compareFn_ can be provided which assures that keys are tested in given order. If provided _compareFn_ is equal to `true`, then order is alphabetical (by key).
Analogous to Array.prototype.forEach. Calls a function for each key-value pair found in object
Optionally _compareFn_ can be provided which assures that properties are iterated in given order. If provided _compareFn_ is equal to `true`, then order is alphabetical (by key).
Analogous to Array.prototype.map. Creates a new object with properties which values are results of calling a provided function on every key-value pair in this object.
Extend _target_ by all own properties of other objects. Properties found in both objects will be overwritten (unless they're not configurable and cannot be overwritten).
Serialize value into string. Differs from [JSON.stringify](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/JSON/stringify) that it serializes also dates, functions and regular expresssions.
Analogous to Array.prototype.some Returns true if any key-value pair satisfies the provided
testing function.
Optionally _compareFn_ can be provided which assures that keys are tested in given order. If provided _compareFn_ is equal to `true`, then order is alphabetical (by key).
Creates an array of results of calling a provided function on every key-value pair in this object.
Optionally _compareFn_ can be provided which assures that results are added in given order. If provided _compareFn_ is equal to `true`, then order is alphabetical (by key).
It's to be used as counterpart to [regExp.sticky](http://people.mozilla.org/~jorendorff/es6-draft.html#sec-get-regexp.prototype.sticky) if it's not implemented.
It's to be used as counterpart to [regExp.unicode](http://people.mozilla.org/~jorendorff/es6-draft.html#sec-get-regexp.prototype.unicode) if it's not implemented.
#### re.match(string) _(es5-ext/reg-exp/#/match)_
[_Introduced with ECMAScript 6_](http://people.mozilla.org/~jorendorff/es6-draft.html#sec-regexp.prototype.match).
[_Introduced with ECMAScript 6_](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/String/normalize).
Returns the Unicode Normalization Form of a given string.
Based on Matsuza's version. Code used for integrated shim can be found at [github.com/walling/unorm](https://github.com/walling/unorm/blob/master/lib/unorm.js)
Simple `replace` version. Doesn't support regular expressions. Replaces just first occurrence of search string. Doesn't support insert patterns, therefore it is safe to replace text with text obtained programmatically (there's no need for additional _\$_ characters escape in such case).
Simple `replace` version. Doesn't support regular expressions. Replaces all occurrences of search string. Doesn't support insert patterns, therefore it is safe to replace text with text obtained programmatically (there's no need for additional _\$_ characters escape in such case).
[_Introduced with ECMAScript 6_](http://people.mozilla.org/~jorendorff/es6-draft.html#sec-string.prototype-@@iterator).
Returns iterator object which traverses all string characters (with respect to unicode symbols)
### Tests
$ npm test
## Security contact information
To report a security vulnerability, please use the [Tidelift security contact](https://tidelift.com/security). Tidelift will coordinate the fix and disclosure.
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