mirror of
https://github.com/Hopiu/postal.js.git
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1258 lines
37 KiB
JavaScript
1258 lines
37 KiB
JavaScript
// Underscore.js 1.3.3
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// (c) 2009-2012 Jeremy Ashkenas, DocumentCloud Inc.
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// Underscore is freely distributable under the MIT license.
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// Portions of Underscore are inspired or borrowed from Prototype,
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// Oliver Steele's Functional, and John Resig's Micro-Templating.
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// For all details and documentation:
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// http://documentcloud.github.com/underscore
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(function () {
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// Baseline setup
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// --------------
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// Establish the root object, `window` in the browser, or `global` on the server.
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var root = this;
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// Save the previous value of the `_` variable.
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var previousUnderscore = root._;
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// Establish the object that gets returned to break out of a loop iteration.
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var breaker = {};
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// Save bytes in the minified (but not gzipped) version:
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var ArrayProto = Array.prototype, ObjProto = Object.prototype, FuncProto = Function.prototype;
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// Create quick reference variables for speed access to core prototypes.
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var slice = ArrayProto.slice,
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unshift = ArrayProto.unshift,
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toString = ObjProto.toString,
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hasOwnProperty = ObjProto.hasOwnProperty;
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// All **ECMAScript 5** native function implementations that we hope to use
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// are declared here.
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var
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nativeForEach = ArrayProto.forEach,
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nativeMap = ArrayProto.map,
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nativeReduce = ArrayProto.reduce,
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nativeReduceRight = ArrayProto.reduceRight,
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nativeFilter = ArrayProto.filter,
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nativeEvery = ArrayProto.every,
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nativeSome = ArrayProto.some,
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nativeIndexOf = ArrayProto.indexOf,
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nativeLastIndexOf = ArrayProto.lastIndexOf,
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nativeIsArray = Array.isArray,
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nativeKeys = Object.keys,
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nativeBind = FuncProto.bind;
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// Create a safe reference to the Underscore object for use below.
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var _ = function ( obj ) {
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return new wrapper( obj );
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};
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// Export the Underscore object for **Node.js**, with
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// backwards-compatibility for the old `require()` API. If we're in
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// the browser, add `_` as a global object via a string identifier,
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// for Closure Compiler "advanced" mode.
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if ( typeof exports !== 'undefined' ) {
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if ( typeof module !== 'undefined' && module.exports ) {
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exports = module.exports = _;
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}
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exports._ = _;
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} else {
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root['_'] = _;
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}
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// Current version.
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_.VERSION = '1.3.3';
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// Collection Functions
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// --------------------
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// The cornerstone, an `each` implementation, aka `forEach`.
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// Handles objects with the built-in `forEach`, arrays, and raw objects.
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// Delegates to **ECMAScript 5**'s native `forEach` if available.
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var each = _.each = _.forEach = function ( obj, iterator, context ) {
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if ( obj == null ) {
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return;
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}
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if ( nativeForEach && obj.forEach === nativeForEach ) {
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obj.forEach( iterator, context );
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} else if ( obj.length === +obj.length ) {
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for ( var i = 0, l = obj.length; i < l; i++ ) {
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if ( i in obj && iterator.call( context, obj[i], i, obj ) === breaker ) {
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return;
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}
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}
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} else {
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for ( var key in obj ) {
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if ( _.has( obj, key ) ) {
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if ( iterator.call( context, obj[key], key, obj ) === breaker ) {
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return;
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}
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}
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}
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}
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};
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// Return the results of applying the iterator to each element.
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// Delegates to **ECMAScript 5**'s native `map` if available.
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_.map = _.collect = function ( obj, iterator, context ) {
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var results = [];
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if ( obj == null ) {
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return results;
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}
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if ( nativeMap && obj.map === nativeMap ) {
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return obj.map( iterator, context );
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}
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each( obj, function ( value, index, list ) {
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results[results.length] = iterator.call( context, value, index, list );
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} );
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if ( obj.length === +obj.length ) {
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results.length = obj.length;
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}
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return results;
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};
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// **Reduce** builds up a single result from a list of values, aka `inject`,
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// or `foldl`. Delegates to **ECMAScript 5**'s native `reduce` if available.
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_.reduce = _.foldl = _.inject = function ( obj, iterator, memo, context ) {
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var initial = arguments.length > 2;
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if ( obj == null ) {
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obj = [];
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}
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if ( nativeReduce && obj.reduce === nativeReduce ) {
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if ( context ) {
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iterator = _.bind( iterator, context );
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}
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return initial ? obj.reduce( iterator, memo ) : obj.reduce( iterator );
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}
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each( obj, function ( value, index, list ) {
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if ( !initial ) {
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memo = value;
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initial = true;
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} else {
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memo = iterator.call( context, memo, value, index, list );
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}
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} );
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if ( !initial ) {
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throw new TypeError( 'Reduce of empty array with no initial value' );
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}
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return memo;
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};
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// The right-associative version of reduce, also known as `foldr`.
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// Delegates to **ECMAScript 5**'s native `reduceRight` if available.
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_.reduceRight = _.foldr = function ( obj, iterator, memo, context ) {
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var initial = arguments.length > 2;
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if ( obj == null ) {
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obj = [];
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}
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if ( nativeReduceRight && obj.reduceRight === nativeReduceRight ) {
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if ( context ) {
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iterator = _.bind( iterator, context );
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}
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return initial ? obj.reduceRight( iterator, memo ) : obj.reduceRight( iterator );
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}
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var reversed = _.toArray( obj ).reverse();
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if ( context && !initial ) {
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iterator = _.bind( iterator, context );
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}
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return initial ? _.reduce( reversed, iterator, memo, context ) : _.reduce( reversed, iterator );
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};
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// Return the first value which passes a truth test. Aliased as `detect`.
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_.find = _.detect = function ( obj, iterator, context ) {
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var result;
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any( obj, function ( value, index, list ) {
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if ( iterator.call( context, value, index, list ) ) {
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result = value;
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return true;
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}
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} );
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return result;
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};
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// Return all the elements that pass a truth test.
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// Delegates to **ECMAScript 5**'s native `filter` if available.
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// Aliased as `select`.
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_.filter = _.select = function ( obj, iterator, context ) {
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var results = [];
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if ( obj == null ) {
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return results;
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}
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if ( nativeFilter && obj.filter === nativeFilter ) {
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return obj.filter( iterator, context );
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}
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each( obj, function ( value, index, list ) {
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if ( iterator.call( context, value, index, list ) ) {
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results[results.length] = value;
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}
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} );
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return results;
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};
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// Return all the elements for which a truth test fails.
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_.reject = function ( obj, iterator, context ) {
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var results = [];
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if ( obj == null ) {
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return results;
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}
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each( obj, function ( value, index, list ) {
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if ( !iterator.call( context, value, index, list ) ) {
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results[results.length] = value;
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}
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} );
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return results;
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};
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// Determine whether all of the elements match a truth test.
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// Delegates to **ECMAScript 5**'s native `every` if available.
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// Aliased as `all`.
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_.every = _.all = function ( obj, iterator, context ) {
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var result = true;
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if ( obj == null ) {
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return result;
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}
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if ( nativeEvery && obj.every === nativeEvery ) {
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return obj.every( iterator, context );
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}
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each( obj, function ( value, index, list ) {
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if ( !(result = result && iterator.call( context, value, index, list )) ) {
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return breaker;
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}
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} );
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return !!result;
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};
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// Determine if at least one element in the object matches a truth test.
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// Delegates to **ECMAScript 5**'s native `some` if available.
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// Aliased as `any`.
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var any = _.some = _.any = function ( obj, iterator, context ) {
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iterator || (iterator = _.identity);
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var result = false;
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if ( obj == null ) {
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return result;
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}
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if ( nativeSome && obj.some === nativeSome ) {
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return obj.some( iterator, context );
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}
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each( obj, function ( value, index, list ) {
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if ( result || (result = iterator.call( context, value, index, list )) ) {
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return breaker;
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}
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} );
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return !!result;
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};
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// Determine if a given value is included in the array or object using `===`.
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// Aliased as `contains`.
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_.include = _.contains = function ( obj, target ) {
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var found = false;
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if ( obj == null ) {
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return found;
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}
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if ( nativeIndexOf && obj.indexOf === nativeIndexOf ) {
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return obj.indexOf( target ) != -1;
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}
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found = any( obj, function ( value ) {
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return value === target;
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} );
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return found;
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};
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// Invoke a method (with arguments) on every item in a collection.
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_.invoke = function ( obj, method ) {
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var args = slice.call( arguments, 2 );
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return _.map( obj, function ( value ) {
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return (_.isFunction( method ) ? method || value : value[method]).apply( value, args );
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} );
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};
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// Convenience version of a common use case of `map`: fetching a property.
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_.pluck = function ( obj, key ) {
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return _.map( obj, function ( value ) {
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return value[key];
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} );
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};
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// Return the maximum element or (element-based computation).
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_.max = function ( obj, iterator, context ) {
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if ( !iterator && _.isArray( obj ) && obj[0] === +obj[0] ) {
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return Math.max.apply( Math, obj );
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}
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if ( !iterator && _.isEmpty( obj ) ) {
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return -Infinity;
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}
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var result = {computed : -Infinity};
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each( obj, function ( value, index, list ) {
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var computed = iterator ? iterator.call( context, value, index, list ) : value;
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computed >= result.computed && (result = {value : value, computed : computed});
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} );
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return result.value;
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};
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// Return the minimum element (or element-based computation).
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_.min = function ( obj, iterator, context ) {
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if ( !iterator && _.isArray( obj ) && obj[0] === +obj[0] ) {
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return Math.min.apply( Math, obj );
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}
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if ( !iterator && _.isEmpty( obj ) ) {
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return Infinity;
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}
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var result = {computed : Infinity};
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each( obj, function ( value, index, list ) {
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var computed = iterator ? iterator.call( context, value, index, list ) : value;
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computed < result.computed && (result = {value : value, computed : computed});
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} );
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return result.value;
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};
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// Shuffle an array.
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_.shuffle = function ( obj ) {
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var shuffled = [], rand;
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each( obj, function ( value, index, list ) {
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rand = Math.floor( Math.random() * (index + 1) );
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shuffled[index] = shuffled[rand];
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shuffled[rand] = value;
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} );
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return shuffled;
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};
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// Sort the object's values by a criterion produced by an iterator.
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_.sortBy = function ( obj, val, context ) {
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var iterator = _.isFunction( val ) ? val : function ( obj ) {
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return obj[val];
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};
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return _.pluck( _.map( obj,
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function ( value, index, list ) {
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return {
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value : value,
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criteria : iterator.call( context, value, index, list )
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};
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} ).sort( function ( left, right ) {
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var a = left.criteria, b = right.criteria;
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if ( a === void 0 ) {
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return 1;
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}
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if ( b === void 0 ) {
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return -1;
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}
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return a < b ? -1 : a > b ? 1 : 0;
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} ), 'value' );
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};
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// Groups the object's values by a criterion. Pass either a string attribute
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// to group by, or a function that returns the criterion.
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_.groupBy = function ( obj, val ) {
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var result = {};
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var iterator = _.isFunction( val ) ? val : function ( obj ) {
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return obj[val];
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};
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each( obj, function ( value, index ) {
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var key = iterator( value, index );
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(result[key] || (result[key] = [])).push( value );
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} );
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return result;
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};
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// Use a comparator function to figure out at what index an object should
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// be inserted so as to maintain order. Uses binary search.
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_.sortedIndex = function ( array, obj, iterator ) {
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iterator || (iterator = _.identity);
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var low = 0, high = array.length;
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while ( low < high ) {
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var mid = (low + high) >> 1;
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iterator( array[mid] ) < iterator( obj ) ? low = mid + 1 : high = mid;
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}
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return low;
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};
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// Safely convert anything iterable into a real, live array.
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_.toArray = function ( obj ) {
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if ( !obj ) {
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return [];
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}
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if ( _.isArray( obj ) ) {
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return slice.call( obj );
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}
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if ( _.isArguments( obj ) ) {
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return slice.call( obj );
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}
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if ( obj.toArray && _.isFunction( obj.toArray ) ) {
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return obj.toArray();
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}
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return _.values( obj );
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};
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// Return the number of elements in an object.
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_.size = function ( obj ) {
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return _.isArray( obj ) ? obj.length : _.keys( obj ).length;
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};
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// Array Functions
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// ---------------
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// Get the first element of an array. Passing **n** will return the first N
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// values in the array. Aliased as `head` and `take`. The **guard** check
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// allows it to work with `_.map`.
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_.first = _.head = _.take = function ( array, n, guard ) {
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return (n != null) && !guard ? slice.call( array, 0, n ) : array[0];
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};
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// Returns everything but the last entry of the array. Especcialy useful on
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// the arguments object. Passing **n** will return all the values in
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// the array, excluding the last N. The **guard** check allows it to work with
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// `_.map`.
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_.initial = function ( array, n, guard ) {
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return slice.call( array, 0, array.length - ((n == null) || guard ? 1 : n) );
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};
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// Get the last element of an array. Passing **n** will return the last N
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// values in the array. The **guard** check allows it to work with `_.map`.
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_.last = function ( array, n, guard ) {
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if ( (n != null) && !guard ) {
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return slice.call( array, Math.max( array.length - n, 0 ) );
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} else {
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return array[array.length - 1];
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}
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};
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// Returns everything but the first entry of the array. Aliased as `tail`.
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// Especially useful on the arguments object. Passing an **index** will return
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// the rest of the values in the array from that index onward. The **guard**
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// check allows it to work with `_.map`.
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_.rest = _.tail = function ( array, index, guard ) {
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return slice.call( array, (index == null) || guard ? 1 : index );
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};
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// Trim out all falsy values from an array.
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_.compact = function ( array ) {
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return _.filter( array, function ( value ) {
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return !!value;
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} );
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};
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// Return a completely flattened version of an array.
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_.flatten = function ( array, shallow ) {
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return _.reduce( array, function ( memo, value ) {
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if ( _.isArray( value ) ) {
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return memo.concat( shallow ? value : _.flatten( value ) );
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}
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memo[memo.length] = value;
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return memo;
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}, [] );
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};
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// Return a version of the array that does not contain the specified value(s).
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_.without = function ( array ) {
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return _.difference( array, slice.call( arguments, 1 ) );
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};
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// Produce a duplicate-free version of the array. If the array has already
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// been sorted, you have the option of using a faster algorithm.
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// Aliased as `unique`.
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_.uniq = _.unique = function ( array, isSorted, iterator ) {
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var initial = iterator ? _.map( array, iterator ) : array;
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var results = [];
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// The `isSorted` flag is irrelevant if the array only contains two elements.
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if ( array.length < 3 ) {
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isSorted = true;
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}
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_.reduce( initial, function ( memo, value, index ) {
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if ( isSorted ? _.last( memo ) !== value || !memo.length : !_.include( memo, value ) ) {
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memo.push( value );
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results.push( array[index] );
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}
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return memo;
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}, [] );
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return results;
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};
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// Produce an array that contains the union: each distinct element from all of
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// the passed-in arrays.
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_.union = function () {
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return _.uniq( _.flatten( arguments, true ) );
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};
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// Produce an array that contains every item shared between all the
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// passed-in arrays. (Aliased as "intersect" for back-compat.)
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_.intersection = _.intersect = function ( array ) {
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var rest = slice.call( arguments, 1 );
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return _.filter( _.uniq( array ), function ( item ) {
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return _.every( rest, function ( other ) {
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return _.indexOf( other, item ) >= 0;
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} );
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} );
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};
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// Take the difference between one array and a number of other arrays.
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// Only the elements present in just the first array will remain.
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_.difference = function ( array ) {
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var rest = _.flatten( slice.call( arguments, 1 ), true );
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return _.filter( array, function ( value ) {
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return !_.include( rest, value );
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} );
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};
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// Zip together multiple lists into a single array -- elements that share
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// an index go together.
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_.zip = function () {
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var args = slice.call( arguments );
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var length = _.max( _.pluck( args, 'length' ) );
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var results = new Array( length );
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for ( var i = 0; i < length; i++ ) {
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results[i] = _.pluck( args, "" + i );
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}
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return results;
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};
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// If the browser doesn't supply us with indexOf (I'm looking at you, **MSIE**),
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// we need this function. Return the position of the first occurrence of an
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// item in an array, or -1 if the item is not included in the array.
|
|
// Delegates to **ECMAScript 5**'s native `indexOf` if available.
|
|
// If the array is large and already in sort order, pass `true`
|
|
// for **isSorted** to use binary search.
|
|
_.indexOf = function ( array, item, isSorted ) {
|
|
if ( array == null ) {
|
|
return -1;
|
|
}
|
|
var i, l;
|
|
if ( isSorted ) {
|
|
i = _.sortedIndex( array, item );
|
|
return array[i] === item ? i : -1;
|
|
}
|
|
if ( nativeIndexOf && array.indexOf === nativeIndexOf ) {
|
|
return array.indexOf( item );
|
|
}
|
|
for ( i = 0, l = array.length; i < l; i++ ) {
|
|
if ( i in array && array[i] === item ) {
|
|
return i;
|
|
}
|
|
}
|
|
return -1;
|
|
};
|
|
|
|
// Delegates to **ECMAScript 5**'s native `lastIndexOf` if available.
|
|
_.lastIndexOf = function ( array, item ) {
|
|
if ( array == null ) {
|
|
return -1;
|
|
}
|
|
if ( nativeLastIndexOf && array.lastIndexOf === nativeLastIndexOf ) {
|
|
return array.lastIndexOf( item );
|
|
}
|
|
var i = array.length;
|
|
while ( i-- ) {
|
|
if ( i in array && array[i] === item ) {
|
|
return i;
|
|
}
|
|
}
|
|
return -1;
|
|
};
|
|
|
|
// Generate an integer Array containing an arithmetic progression. A port of
|
|
// the native Python `range()` function. See
|
|
// [the Python documentation](http://docs.python.org/library/functions.html#range).
|
|
_.range = function ( start, stop, step ) {
|
|
if ( arguments.length <= 1 ) {
|
|
stop = start || 0;
|
|
start = 0;
|
|
}
|
|
step = arguments[2] || 1;
|
|
|
|
var len = Math.max( Math.ceil( (stop - start) / step ), 0 );
|
|
var idx = 0;
|
|
var range = new Array( len );
|
|
|
|
while ( idx < len ) {
|
|
range[idx++] = start;
|
|
start += step;
|
|
}
|
|
|
|
return range;
|
|
};
|
|
|
|
// Function (ahem) Functions
|
|
// ------------------
|
|
|
|
// Reusable constructor function for prototype setting.
|
|
var ctor = function () {
|
|
};
|
|
|
|
// Create a function bound to a given object (assigning `this`, and arguments,
|
|
// optionally). Binding with arguments is also known as `curry`.
|
|
// Delegates to **ECMAScript 5**'s native `Function.bind` if available.
|
|
// We check for `func.bind` first, to fail fast when `func` is undefined.
|
|
_.bind = function bind( func, context ) {
|
|
var bound, args;
|
|
if ( func.bind === nativeBind && nativeBind ) {
|
|
return nativeBind.apply( func, slice.call( arguments, 1 ) );
|
|
}
|
|
if ( !_.isFunction( func ) ) {
|
|
throw new TypeError;
|
|
}
|
|
args = slice.call( arguments, 2 );
|
|
return bound = function () {
|
|
if ( !(this instanceof bound) ) {
|
|
return func.apply( context, args.concat( slice.call( arguments ) ) );
|
|
}
|
|
ctor.prototype = func.prototype;
|
|
var self = new ctor;
|
|
var result = func.apply( self, args.concat( slice.call( arguments ) ) );
|
|
if ( Object( result ) === result ) {
|
|
return result;
|
|
}
|
|
return self;
|
|
};
|
|
};
|
|
|
|
// Bind all of an object's methods to that object. Useful for ensuring that
|
|
// all callbacks defined on an object belong to it.
|
|
_.bindAll = function ( obj ) {
|
|
var funcs = slice.call( arguments, 1 );
|
|
if ( funcs.length == 0 ) {
|
|
funcs = _.functions( obj );
|
|
}
|
|
each( funcs, function ( f ) {
|
|
obj[f] = _.bind( obj[f], obj );
|
|
} );
|
|
return obj;
|
|
};
|
|
|
|
// Memoize an expensive function by storing its results.
|
|
_.memoize = function ( func, hasher ) {
|
|
var memo = {};
|
|
hasher || (hasher = _.identity);
|
|
return function () {
|
|
var key = hasher.apply( this, arguments );
|
|
return _.has( memo, key ) ? memo[key] : (memo[key] = func.apply( this, arguments ));
|
|
};
|
|
};
|
|
|
|
// Delays a function for the given number of milliseconds, and then calls
|
|
// it with the arguments supplied.
|
|
_.delay = function ( func, wait ) {
|
|
var args = slice.call( arguments, 2 );
|
|
return setTimeout( function () {
|
|
return func.apply( null, args );
|
|
}, wait );
|
|
};
|
|
|
|
// Defers a function, scheduling it to run after the current call stack has
|
|
// cleared.
|
|
_.defer = function ( func ) {
|
|
return _.delay.apply( _, [func, 1].concat( slice.call( arguments, 1 ) ) );
|
|
};
|
|
|
|
// Returns a function, that, when invoked, will only be triggered at most once
|
|
// during a given window of time.
|
|
_.throttle = function ( func, wait ) {
|
|
var context, args, timeout, throttling, more, result;
|
|
var whenDone = _.debounce( function () {
|
|
more = throttling = false;
|
|
}, wait );
|
|
return function () {
|
|
context = this;
|
|
args = arguments;
|
|
var later = function () {
|
|
timeout = null;
|
|
if ( more ) {
|
|
func.apply( context, args );
|
|
}
|
|
whenDone();
|
|
};
|
|
if ( !timeout ) {
|
|
timeout = setTimeout( later, wait );
|
|
}
|
|
if ( throttling ) {
|
|
more = true;
|
|
} else {
|
|
result = func.apply( context, args );
|
|
}
|
|
whenDone();
|
|
throttling = true;
|
|
return result;
|
|
};
|
|
};
|
|
|
|
// Returns a function, that, as long as it continues to be invoked, will not
|
|
// be triggered. The function will be called after it stops being called for
|
|
// N milliseconds. If `immediate` is passed, trigger the function on the
|
|
// leading edge, instead of the trailing.
|
|
_.debounce = function ( func, wait, immediate ) {
|
|
var timeout;
|
|
return function () {
|
|
var context = this, args = arguments;
|
|
var later = function () {
|
|
timeout = null;
|
|
if ( !immediate ) {
|
|
func.apply( context, args );
|
|
}
|
|
};
|
|
if ( immediate && !timeout ) {
|
|
func.apply( context, args );
|
|
}
|
|
clearTimeout( timeout );
|
|
timeout = setTimeout( later, wait );
|
|
};
|
|
};
|
|
|
|
// Returns a function that will be executed at most one time, no matter how
|
|
// often you call it. Useful for lazy initialization.
|
|
_.once = function ( func ) {
|
|
var ran = false, memo;
|
|
return function () {
|
|
if ( ran ) {
|
|
return memo;
|
|
}
|
|
ran = true;
|
|
return memo = func.apply( this, arguments );
|
|
};
|
|
};
|
|
|
|
// Returns the first function passed as an argument to the second,
|
|
// allowing you to adjust arguments, run code before and after, and
|
|
// conditionally execute the original function.
|
|
_.wrap = function ( func, wrapper ) {
|
|
return function () {
|
|
var args = [func].concat( slice.call( arguments, 0 ) );
|
|
return wrapper.apply( this, args );
|
|
};
|
|
};
|
|
|
|
// Returns a function that is the composition of a list of functions, each
|
|
// consuming the return value of the function that follows.
|
|
_.compose = function () {
|
|
var funcs = arguments;
|
|
return function () {
|
|
var args = arguments;
|
|
for ( var i = funcs.length - 1; i >= 0; i-- ) {
|
|
args = [funcs[i].apply( this, args )];
|
|
}
|
|
return args[0];
|
|
};
|
|
};
|
|
|
|
// Returns a function that will only be executed after being called N times.
|
|
_.after = function ( times, func ) {
|
|
if ( times <= 0 ) {
|
|
return func();
|
|
}
|
|
return function () {
|
|
if ( --times < 1 ) {
|
|
return func.apply( this, arguments );
|
|
}
|
|
};
|
|
};
|
|
|
|
// Object Functions
|
|
// ----------------
|
|
|
|
// Retrieve the names of an object's properties.
|
|
// Delegates to **ECMAScript 5**'s native `Object.keys`
|
|
_.keys = nativeKeys || function ( obj ) {
|
|
if ( obj !== Object( obj ) ) {
|
|
throw new TypeError( 'Invalid object' );
|
|
}
|
|
var keys = [];
|
|
for ( var key in obj ) {
|
|
if ( _.has( obj, key ) ) {
|
|
keys[keys.length] = key;
|
|
}
|
|
}
|
|
return keys;
|
|
};
|
|
|
|
// Retrieve the values of an object's properties.
|
|
_.values = function ( obj ) {
|
|
return _.map( obj, _.identity );
|
|
};
|
|
|
|
// Return a sorted list of the function names available on the object.
|
|
// Aliased as `methods`
|
|
_.functions = _.methods = function ( obj ) {
|
|
var names = [];
|
|
for ( var key in obj ) {
|
|
if ( _.isFunction( obj[key] ) ) {
|
|
names.push( key );
|
|
}
|
|
}
|
|
return names.sort();
|
|
};
|
|
|
|
// Extend a given object with all the properties in passed-in object(s).
|
|
_.extend = function ( obj ) {
|
|
each( slice.call( arguments, 1 ), function ( source ) {
|
|
for ( var prop in source ) {
|
|
obj[prop] = source[prop];
|
|
}
|
|
} );
|
|
return obj;
|
|
};
|
|
|
|
// Return a copy of the object only containing the whitelisted properties.
|
|
_.pick = function ( obj ) {
|
|
var result = {};
|
|
each( _.flatten( slice.call( arguments, 1 ) ), function ( key ) {
|
|
if ( key in obj ) {
|
|
result[key] = obj[key];
|
|
}
|
|
} );
|
|
return result;
|
|
};
|
|
|
|
// Fill in a given object with default properties.
|
|
_.defaults = function ( obj ) {
|
|
each( slice.call( arguments, 1 ), function ( source ) {
|
|
for ( var prop in source ) {
|
|
if ( obj[prop] == null ) {
|
|
obj[prop] = source[prop];
|
|
}
|
|
}
|
|
} );
|
|
return obj;
|
|
};
|
|
|
|
// Create a (shallow-cloned) duplicate of an object.
|
|
_.clone = function ( obj ) {
|
|
if ( !_.isObject( obj ) ) {
|
|
return obj;
|
|
}
|
|
return _.isArray( obj ) ? obj.slice() : _.extend( {}, obj );
|
|
};
|
|
|
|
// Invokes interceptor with the obj, and then returns obj.
|
|
// The primary purpose of this method is to "tap into" a method chain, in
|
|
// order to perform operations on intermediate results within the chain.
|
|
_.tap = function ( obj, interceptor ) {
|
|
interceptor( obj );
|
|
return obj;
|
|
};
|
|
|
|
// Internal recursive comparison function.
|
|
function eq( a, b, stack ) {
|
|
// Identical objects are equal. `0 === -0`, but they aren't identical.
|
|
// See the Harmony `egal` proposal: http://wiki.ecmascript.org/doku.php?id=harmony:egal.
|
|
if ( a === b ) {
|
|
return a !== 0 || 1 / a == 1 / b;
|
|
}
|
|
// A strict comparison is necessary because `null == undefined`.
|
|
if ( a == null || b == null ) {
|
|
return a === b;
|
|
}
|
|
// Unwrap any wrapped objects.
|
|
if ( a._chain ) {
|
|
a = a._wrapped;
|
|
}
|
|
if ( b._chain ) {
|
|
b = b._wrapped;
|
|
}
|
|
// Invoke a custom `isEqual` method if one is provided.
|
|
if ( a.isEqual && _.isFunction( a.isEqual ) ) {
|
|
return a.isEqual( b );
|
|
}
|
|
if ( b.isEqual && _.isFunction( b.isEqual ) ) {
|
|
return b.isEqual( a );
|
|
}
|
|
// Compare `[[Class]]` names.
|
|
var className = toString.call( a );
|
|
if ( className != toString.call( b ) ) {
|
|
return false;
|
|
}
|
|
switch ( className ) {
|
|
// Strings, numbers, dates, and booleans are compared by value.
|
|
case '[object String]':
|
|
// Primitives and their corresponding object wrappers are equivalent; thus, `"5"` is
|
|
// equivalent to `new String("5")`.
|
|
return a == String( b );
|
|
case '[object Number]':
|
|
// `NaN`s are equivalent, but non-reflexive. An `egal` comparison is performed for
|
|
// other numeric values.
|
|
return a != +a ? b != +b : (a == 0 ? 1 / a == 1 / b : a == +b);
|
|
case '[object Date]':
|
|
case '[object Boolean]':
|
|
// Coerce dates and booleans to numeric primitive values. Dates are compared by their
|
|
// millisecond representations. Note that invalid dates with millisecond representations
|
|
// of `NaN` are not equivalent.
|
|
return +a == +b;
|
|
// RegExps are compared by their source patterns and flags.
|
|
case '[object RegExp]':
|
|
return a.source == b.source &&
|
|
a.global == b.global &&
|
|
a.multiline == b.multiline &&
|
|
a.ignoreCase == b.ignoreCase;
|
|
}
|
|
if ( typeof a != 'object' || typeof b != 'object' ) {
|
|
return false;
|
|
}
|
|
// Assume equality for cyclic structures. The algorithm for detecting cyclic
|
|
// structures is adapted from ES 5.1 section 15.12.3, abstract operation `JO`.
|
|
var length = stack.length;
|
|
while ( length-- ) {
|
|
// Linear search. Performance is inversely proportional to the number of
|
|
// unique nested structures.
|
|
if ( stack[length] == a ) {
|
|
return true;
|
|
}
|
|
}
|
|
// Add the first object to the stack of traversed objects.
|
|
stack.push( a );
|
|
var size = 0, result = true;
|
|
// Recursively compare objects and arrays.
|
|
if ( className == '[object Array]' ) {
|
|
// Compare array lengths to determine if a deep comparison is necessary.
|
|
size = a.length;
|
|
result = size == b.length;
|
|
if ( result ) {
|
|
// Deep compare the contents, ignoring non-numeric properties.
|
|
while ( size-- ) {
|
|
// Ensure commutative equality for sparse arrays.
|
|
if ( !(result = size in a == size in b && eq( a[size], b[size], stack )) ) {
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
} else {
|
|
// Objects with different constructors are not equivalent.
|
|
if ( 'constructor' in a != 'constructor' in b || a.constructor != b.constructor ) {
|
|
return false;
|
|
}
|
|
// Deep compare objects.
|
|
for ( var key in a ) {
|
|
if ( _.has( a, key ) ) {
|
|
// Count the expected number of properties.
|
|
size++;
|
|
// Deep compare each member.
|
|
if ( !(result = _.has( b, key ) && eq( a[key], b[key], stack )) ) {
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
// Ensure that both objects contain the same number of properties.
|
|
if ( result ) {
|
|
for ( key in b ) {
|
|
if ( _.has( b, key ) && !(size--) ) {
|
|
break;
|
|
}
|
|
}
|
|
result = !size;
|
|
}
|
|
}
|
|
// Remove the first object from the stack of traversed objects.
|
|
stack.pop();
|
|
return result;
|
|
}
|
|
|
|
// Perform a deep comparison to check if two objects are equal.
|
|
_.isEqual = function ( a, b ) {
|
|
return eq( a, b, [] );
|
|
};
|
|
|
|
// Is a given array, string, or object empty?
|
|
// An "empty" object has no enumerable own-properties.
|
|
_.isEmpty = function ( obj ) {
|
|
if ( obj == null ) {
|
|
return true;
|
|
}
|
|
if ( _.isArray( obj ) || _.isString( obj ) ) {
|
|
return obj.length === 0;
|
|
}
|
|
for ( var key in obj ) {
|
|
if ( _.has( obj, key ) ) {
|
|
return false;
|
|
}
|
|
}
|
|
return true;
|
|
};
|
|
|
|
// Is a given value a DOM element?
|
|
_.isElement = function ( obj ) {
|
|
return !!(obj && obj.nodeType == 1);
|
|
};
|
|
|
|
// Is a given value an array?
|
|
// Delegates to ECMA5's native Array.isArray
|
|
_.isArray = nativeIsArray || function ( obj ) {
|
|
return toString.call( obj ) == '[object Array]';
|
|
};
|
|
|
|
// Is a given variable an object?
|
|
_.isObject = function ( obj ) {
|
|
return obj === Object( obj );
|
|
};
|
|
|
|
// Is a given variable an arguments object?
|
|
_.isArguments = function ( obj ) {
|
|
return toString.call( obj ) == '[object Arguments]';
|
|
};
|
|
if ( !_.isArguments( arguments ) ) {
|
|
_.isArguments = function ( obj ) {
|
|
return !!(obj && _.has( obj, 'callee' ));
|
|
};
|
|
}
|
|
|
|
// Is a given value a function?
|
|
_.isFunction = function ( obj ) {
|
|
return toString.call( obj ) == '[object Function]';
|
|
};
|
|
|
|
// Is a given value a string?
|
|
_.isString = function ( obj ) {
|
|
return toString.call( obj ) == '[object String]';
|
|
};
|
|
|
|
// Is a given value a number?
|
|
_.isNumber = function ( obj ) {
|
|
return toString.call( obj ) == '[object Number]';
|
|
};
|
|
|
|
// Is a given object a finite number?
|
|
_.isFinite = function ( obj ) {
|
|
return _.isNumber( obj ) && isFinite( obj );
|
|
};
|
|
|
|
// Is the given value `NaN`?
|
|
_.isNaN = function ( obj ) {
|
|
// `NaN` is the only value for which `===` is not reflexive.
|
|
return obj !== obj;
|
|
};
|
|
|
|
// Is a given value a boolean?
|
|
_.isBoolean = function ( obj ) {
|
|
return obj === true || obj === false || toString.call( obj ) == '[object Boolean]';
|
|
};
|
|
|
|
// Is a given value a date?
|
|
_.isDate = function ( obj ) {
|
|
return toString.call( obj ) == '[object Date]';
|
|
};
|
|
|
|
// Is the given value a regular expression?
|
|
_.isRegExp = function ( obj ) {
|
|
return toString.call( obj ) == '[object RegExp]';
|
|
};
|
|
|
|
// Is a given value equal to null?
|
|
_.isNull = function ( obj ) {
|
|
return obj === null;
|
|
};
|
|
|
|
// Is a given variable undefined?
|
|
_.isUndefined = function ( obj ) {
|
|
return obj === void 0;
|
|
};
|
|
|
|
// Has own property?
|
|
_.has = function ( obj, key ) {
|
|
return hasOwnProperty.call( obj, key );
|
|
};
|
|
|
|
// Utility Functions
|
|
// -----------------
|
|
|
|
// Run Underscore.js in *noConflict* mode, returning the `_` variable to its
|
|
// previous owner. Returns a reference to the Underscore object.
|
|
_.noConflict = function () {
|
|
root._ = previousUnderscore;
|
|
return this;
|
|
};
|
|
|
|
// Keep the identity function around for default iterators.
|
|
_.identity = function ( value ) {
|
|
return value;
|
|
};
|
|
|
|
// Run a function **n** times.
|
|
_.times = function ( n, iterator, context ) {
|
|
for ( var i = 0; i < n; i++ ) {
|
|
iterator.call( context, i );
|
|
}
|
|
};
|
|
|
|
// Escape a string for HTML interpolation.
|
|
_.escape = function ( string ) {
|
|
return ('' + string).replace( /&/g, '&' ).replace( /</g, '<' ).replace( />/g, '>' ).replace( /"/g, '"' ).replace( /'/g, ''' ).replace( /\//g, '/' );
|
|
};
|
|
|
|
// If the value of the named property is a function then invoke it;
|
|
// otherwise, return it.
|
|
_.result = function ( object, property ) {
|
|
if ( object == null ) {
|
|
return null;
|
|
}
|
|
var value = object[property];
|
|
return _.isFunction( value ) ? value.call( object ) : value;
|
|
};
|
|
|
|
// Add your own custom functions to the Underscore object, ensuring that
|
|
// they're correctly added to the OOP wrapper as well.
|
|
_.mixin = function ( obj ) {
|
|
each( _.functions( obj ), function ( name ) {
|
|
addToWrapper( name, _[name] = obj[name] );
|
|
} );
|
|
};
|
|
|
|
// Generate a unique integer id (unique within the entire client session).
|
|
// Useful for temporary DOM ids.
|
|
var idCounter = 0;
|
|
_.uniqueId = function ( prefix ) {
|
|
var id = idCounter++;
|
|
return prefix ? prefix + id : id;
|
|
};
|
|
|
|
// By default, Underscore uses ERB-style template delimiters, change the
|
|
// following template settings to use alternative delimiters.
|
|
_.templateSettings = {
|
|
evaluate : /<%([\s\S]+?)%>/g,
|
|
interpolate : /<%=([\s\S]+?)%>/g,
|
|
escape : /<%-([\s\S]+?)%>/g
|
|
};
|
|
|
|
// When customizing `templateSettings`, if you don't want to define an
|
|
// interpolation, evaluation or escaping regex, we need one that is
|
|
// guaranteed not to match.
|
|
var noMatch = /.^/;
|
|
|
|
// Certain characters need to be escaped so that they can be put into a
|
|
// string literal.
|
|
var escapes = {
|
|
'\\' : '\\',
|
|
"'" : "'",
|
|
'r' : '\r',
|
|
'n' : '\n',
|
|
't' : '\t',
|
|
'u2028' : '\u2028',
|
|
'u2029' : '\u2029'
|
|
};
|
|
|
|
for ( var p in escapes ) {
|
|
escapes[escapes[p]] = p;
|
|
}
|
|
var escaper = /\\|'|\r|\n|\t|\u2028|\u2029/g;
|
|
var unescaper = /\\(\\|'|r|n|t|u2028|u2029)/g;
|
|
|
|
// Within an interpolation, evaluation, or escaping, remove HTML escaping
|
|
// that had been previously added.
|
|
var unescape = function ( code ) {
|
|
return code.replace( unescaper, function ( match, escape ) {
|
|
return escapes[escape];
|
|
} );
|
|
};
|
|
|
|
// JavaScript micro-templating, similar to John Resig's implementation.
|
|
// Underscore templating handles arbitrary delimiters, preserves whitespace,
|
|
// and correctly escapes quotes within interpolated code.
|
|
_.template = function ( text, data, settings ) {
|
|
settings = _.defaults( settings || {}, _.templateSettings );
|
|
|
|
// Compile the template source, taking care to escape characters that
|
|
// cannot be included in a string literal and then unescape them in code
|
|
// blocks.
|
|
var source = "__p+='" + text
|
|
.replace( escaper, function ( match ) {
|
|
return '\\' + escapes[match];
|
|
} )
|
|
.replace( settings.escape || noMatch, function ( match, code ) {
|
|
return "'+\n_.escape(" + unescape( code ) + ")+\n'";
|
|
} )
|
|
.replace( settings.interpolate || noMatch, function ( match, code ) {
|
|
return "'+\n(" + unescape( code ) + ")+\n'";
|
|
} )
|
|
.replace( settings.evaluate || noMatch, function ( match, code ) {
|
|
return "';\n" + unescape( code ) + "\n;__p+='";
|
|
} ) + "';\n";
|
|
|
|
// If a variable is not specified, place data values in local scope.
|
|
if ( !settings.variable ) {
|
|
source = 'with(obj||{}){\n' + source + '}\n';
|
|
}
|
|
|
|
source = "var __p='';" +
|
|
"var print=function(){__p+=Array.prototype.join.call(arguments, '')};\n" +
|
|
source + "return __p;\n";
|
|
|
|
var render = new Function( settings.variable || 'obj', '_', source );
|
|
if ( data ) {
|
|
return render( data, _ );
|
|
}
|
|
var template = function ( data ) {
|
|
return render.call( this, data, _ );
|
|
};
|
|
|
|
// Provide the compiled function source as a convenience for build time
|
|
// precompilation.
|
|
template.source = 'function(' + (settings.variable || 'obj') + '){\n' +
|
|
source + '}';
|
|
|
|
return template;
|
|
};
|
|
|
|
// Add a "chain" function, which will delegate to the wrapper.
|
|
_.chain = function ( obj ) {
|
|
return _( obj ).chain();
|
|
};
|
|
|
|
// The OOP Wrapper
|
|
// ---------------
|
|
|
|
// If Underscore is called as a function, it returns a wrapped object that
|
|
// can be used OO-style. This wrapper holds altered versions of all the
|
|
// underscore functions. Wrapped objects may be chained.
|
|
var wrapper = function ( obj ) {
|
|
this._wrapped = obj;
|
|
};
|
|
|
|
// Expose `wrapper.prototype` as `_.prototype`
|
|
_.prototype = wrapper.prototype;
|
|
|
|
// Helper function to continue chaining intermediate results.
|
|
var result = function ( obj, chain ) {
|
|
return chain ? _( obj ).chain() : obj;
|
|
};
|
|
|
|
// A method to easily add functions to the OOP wrapper.
|
|
var addToWrapper = function ( name, func ) {
|
|
wrapper.prototype[name] = function () {
|
|
var args = slice.call( arguments );
|
|
unshift.call( args, this._wrapped );
|
|
return result( func.apply( _, args ), this._chain );
|
|
};
|
|
};
|
|
|
|
// Add all of the Underscore functions to the wrapper object.
|
|
_.mixin( _ );
|
|
|
|
// Add all mutator Array functions to the wrapper.
|
|
each( ['pop', 'push', 'reverse', 'shift', 'sort', 'splice', 'unshift'], function ( name ) {
|
|
var method = ArrayProto[name];
|
|
wrapper.prototype[name] = function () {
|
|
var wrapped = this._wrapped;
|
|
method.apply( wrapped, arguments );
|
|
var length = wrapped.length;
|
|
if ( (name == 'shift' || name == 'splice') && length === 0 ) {
|
|
delete wrapped[0];
|
|
}
|
|
return result( wrapped, this._chain );
|
|
};
|
|
} );
|
|
|
|
// Add all accessor Array functions to the wrapper.
|
|
each( ['concat', 'join', 'slice'], function ( name ) {
|
|
var method = ArrayProto[name];
|
|
wrapper.prototype[name] = function () {
|
|
return result( method.apply( this._wrapped, arguments ), this._chain );
|
|
};
|
|
} );
|
|
|
|
// Start chaining a wrapped Underscore object.
|
|
wrapper.prototype.chain = function () {
|
|
this._chain = true;
|
|
return this;
|
|
};
|
|
|
|
// Extracts the result from a wrapped and chained object.
|
|
wrapper.prototype.value = function () {
|
|
return this._wrapped;
|
|
};
|
|
|
|
}).call( this );
|