1227 lines
40 KiB
JavaScript
1227 lines
40 KiB
JavaScript
// Underscore.js 1.4.4
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// http://underscorejs.org
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// (c) 2009-2013 Jeremy Ashkenas, DocumentCloud Inc.
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// Underscore may be freely distributed under the MIT license.
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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 push = ArrayProto.push,
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slice = ArrayProto.slice,
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concat = ArrayProto.concat,
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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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if (obj instanceof _) return obj;
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if (!(this instanceof _)) return new _(obj);
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this._wrapped = 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 = '1.4.4';
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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) return;
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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 (iterator.call(context, obj[i], i, obj) === breaker) return;
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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) return;
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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) return results;
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if (nativeMap && obj.map === nativeMap) return obj.map(iterator, context);
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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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return results;
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};
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var reduceError = 'Reduce of empty array with no initial value';
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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) obj = [];
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if (nativeReduce && obj.reduce === nativeReduce) {
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if (context) iterator = _.bind(iterator, context);
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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) throw new TypeError(reduceError);
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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) obj = [];
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if (nativeReduceRight && obj.reduceRight === nativeReduceRight) {
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if (context) iterator = _.bind(iterator, context);
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return initial ? obj.reduceRight(iterator, memo) : obj.reduceRight(iterator);
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}
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var length = obj.length;
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if (length !== +length) {
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var keys = _.keys(obj);
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length = keys.length;
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}
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each(obj, function(value, index, list) {
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index = keys ? keys[--length] : --length;
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if (!initial) {
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memo = obj[index];
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initial = true;
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} else {
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memo = iterator.call(context, memo, obj[index], index, list);
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}
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});
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if (!initial) throw new TypeError(reduceError);
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return memo;
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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) return results;
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if (nativeFilter && obj.filter === nativeFilter) return obj.filter(iterator, context);
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each(obj, function(value, index, list) {
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if (iterator.call(context, value, index, list)) results[results.length] = value;
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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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return _.filter(obj, function(value, index, list) {
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return !iterator.call(context, value, index, list);
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}, context);
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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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iterator || (iterator = _.identity);
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var result = true;
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if (obj == null) return result;
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if (nativeEvery && obj.every === nativeEvery) return obj.every(iterator, context);
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each(obj, function(value, index, list) {
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if (!(result = result && iterator.call(context, value, index, list))) return breaker;
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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) return result;
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if (nativeSome && obj.some === nativeSome) return obj.some(iterator, context);
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each(obj, function(value, index, list) {
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if (result || (result = iterator.call(context, value, index, list))) return breaker;
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});
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return !!result;
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};
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// Determine if the array or object contains a given value (using `===`).
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// Aliased as `include`.
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_.contains = _.include = function(obj, target) {
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if (obj == null) return false;
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if (nativeIndexOf && obj.indexOf === nativeIndexOf) return obj.indexOf(target) != -1;
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return any(obj, function(value) {
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return value === target;
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});
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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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var isFunc = _.isFunction(method);
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return _.map(obj, function(value) {
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return (isFunc ? method : 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){ return value[key]; });
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};
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// Convenience version of a common use case of `filter`: selecting only objects
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// containing specific `key:value` pairs.
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_.where = function(obj, attrs, first) {
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if (_.isEmpty(attrs)) return first ? null : [];
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return _[first ? 'find' : 'filter'](obj, function(value) {
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for (var key in attrs) {
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if (attrs[key] !== value[key]) return false;
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}
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return true;
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});
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};
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// Convenience version of a common use case of `find`: getting the first object
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// containing specific `key:value` pairs.
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_.findWhere = function(obj, attrs) {
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return _.where(obj, attrs, true);
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};
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// Return the maximum element or (element-based computation).
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// Can't optimize arrays of integers longer than 65,535 elements.
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// See: https://bugs.webkit.org/show_bug.cgi?id=80797
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_.max = function(obj, iterator, context) {
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if (!iterator && _.isArray(obj) && obj[0] === +obj[0] && obj.length < 65535) {
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return Math.max.apply(Math, obj);
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}
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if (!iterator && _.isEmpty(obj)) return -Infinity;
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var result = {computed : -Infinity, value: -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] && obj.length < 65535) {
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return Math.min.apply(Math, obj);
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}
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if (!iterator && _.isEmpty(obj)) return Infinity;
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var result = {computed : Infinity, value: 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 rand;
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var index = 0;
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var shuffled = [];
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each(obj, function(value) {
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rand = _.random(index++);
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shuffled[index - 1] = 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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// An internal function to generate lookup iterators.
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var lookupIterator = function(value) {
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return _.isFunction(value) ? value : function(obj){ return obj[value]; };
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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, value, context) {
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var iterator = lookupIterator(value);
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return _.pluck(_.map(obj, function(value, index, list) {
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return {
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value : value,
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index : index,
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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;
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var b = right.criteria;
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if (a !== b) {
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if (a > b || a === void 0) return 1;
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if (a < b || b === void 0) return -1;
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}
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return left.index < right.index ? -1 : 1;
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}), 'value');
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};
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// An internal function used for aggregate "group by" operations.
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var group = function(obj, value, context, behavior) {
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var result = {};
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var iterator = lookupIterator(value || _.identity);
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each(obj, function(value, index) {
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var key = iterator.call(context, value, index, obj);
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behavior(result, key, value);
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});
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return result;
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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, value, context) {
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return group(obj, value, context, function(result, key, value) {
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(_.has(result, key) ? result[key] : (result[key] = [])).push(value);
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});
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};
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// Counts instances of an object that group by a certain criterion. Pass
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// either a string attribute to count by, or a function that returns the
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// criterion.
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_.countBy = function(obj, value, context) {
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return group(obj, value, context, function(result, key) {
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if (!_.has(result, key)) result[key] = 0;
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result[key]++;
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});
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};
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// Use a comparator function to figure out the smallest index at which
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// an object should be inserted so as to maintain order. Uses binary search.
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_.sortedIndex = function(array, obj, iterator, context) {
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iterator = iterator == null ? _.identity : lookupIterator(iterator);
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var value = iterator.call(context, obj);
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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.call(context, array[mid]) < value ? 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) return [];
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if (_.isArray(obj)) return slice.call(obj);
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if (obj.length === +obj.length) return _.map(obj, _.identity);
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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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if (obj == null) return 0;
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return (obj.length === +obj.length) ? 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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if (array == null) return void 0;
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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. Especially 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 (array == null) return void 0;
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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` and `drop`.
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// Especially useful on the arguments object. Passing an **n** will return
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// the rest N values in the array. The **guard**
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// check allows it to work with `_.map`.
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_.rest = _.tail = _.drop = function(array, n, guard) {
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return slice.call(array, (n == null) || guard ? 1 : n);
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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, _.identity);
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};
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// Internal implementation of a recursive `flatten` function.
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var flatten = function(input, shallow, output) {
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each(input, function(value) {
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if (_.isArray(value)) {
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shallow ? push.apply(output, value) : flatten(value, shallow, output);
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} else {
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output.push(value);
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}
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});
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return output;
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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 flatten(array, shallow, []);
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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, context) {
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if (_.isFunction(isSorted)) {
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context = iterator;
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iterator = isSorted;
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isSorted = false;
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}
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var initial = iterator ? _.map(array, iterator, context) : array;
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var results = [];
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var seen = [];
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each(initial, function(value, index) {
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if (isSorted ? (!index || seen[seen.length - 1] !== value) : !_.contains(seen, value)) {
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seen.push(value);
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results.push(array[index]);
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}
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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(concat.apply(ArrayProto, arguments));
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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.
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_.intersection = 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 = concat.apply(ArrayProto, slice.call(arguments, 1));
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return _.filter(array, function(value){ return !_.contains(rest, value); });
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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);
|
|
var length = _.max(_.pluck(args, 'length'));
|
|
var results = new Array(length);
|
|
for (var i = 0; i < length; i++) {
|
|
results[i] = _.pluck(args, "" + i);
|
|
}
|
|
return results;
|
|
};
|
|
|
|
// Converts lists into objects. Pass either a single array of `[key, value]`
|
|
// pairs, or two parallel arrays of the same length -- one of keys, and one of
|
|
// the corresponding values.
|
|
_.object = function(list, values) {
|
|
if (list == null) return {};
|
|
var result = {};
|
|
for (var i = 0, l = list.length; i < l; i++) {
|
|
if (values) {
|
|
result[list[i]] = values[i];
|
|
} else {
|
|
result[list[i][0]] = list[i][1];
|
|
}
|
|
}
|
|
return result;
|
|
};
|
|
|
|
// If the browser doesn't supply us with indexOf (I'm looking at you, **MSIE**),
|
|
// we need this function. Return the position of the first occurrence of an
|
|
// 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 = 0, l = array.length;
|
|
if (isSorted) {
|
|
if (typeof isSorted == 'number') {
|
|
i = (isSorted < 0 ? Math.max(0, l + isSorted) : isSorted);
|
|
} else {
|
|
i = _.sortedIndex(array, item);
|
|
return array[i] === item ? i : -1;
|
|
}
|
|
}
|
|
if (nativeIndexOf && array.indexOf === nativeIndexOf) return array.indexOf(item, isSorted);
|
|
for (; i < l; i++) if (array[i] === item) return i;
|
|
return -1;
|
|
};
|
|
|
|
// Delegates to **ECMAScript 5**'s native `lastIndexOf` if available.
|
|
_.lastIndexOf = function(array, item, from) {
|
|
if (array == null) return -1;
|
|
var hasIndex = from != null;
|
|
if (nativeLastIndexOf && array.lastIndexOf === nativeLastIndexOf) {
|
|
return hasIndex ? array.lastIndexOf(item, from) : array.lastIndexOf(item);
|
|
}
|
|
var i = (hasIndex ? from : array.length);
|
|
while (i--) if (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
|
|
// ------------------
|
|
|
|
// Create a function bound to a given object (assigning `this`, and arguments,
|
|
// optionally). Delegates to **ECMAScript 5**'s native `Function.bind` if
|
|
// available.
|
|
_.bind = function(func, context) {
|
|
if (func.bind === nativeBind && nativeBind) return nativeBind.apply(func, slice.call(arguments, 1));
|
|
var args = slice.call(arguments, 2);
|
|
return function() {
|
|
return func.apply(context, args.concat(slice.call(arguments)));
|
|
};
|
|
};
|
|
|
|
// Partially apply a function by creating a version that has had some of its
|
|
// arguments pre-filled, without changing its dynamic `this` context.
|
|
_.partial = function(func) {
|
|
var args = slice.call(arguments, 1);
|
|
return function() {
|
|
return func.apply(this, args.concat(slice.call(arguments)));
|
|
};
|
|
};
|
|
|
|
// 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, result;
|
|
var previous = 0;
|
|
var later = function() {
|
|
previous = new Date;
|
|
timeout = null;
|
|
result = func.apply(context, args);
|
|
};
|
|
return function() {
|
|
var now = new Date;
|
|
var remaining = wait - (now - previous);
|
|
context = this;
|
|
args = arguments;
|
|
if (remaining <= 0) {
|
|
clearTimeout(timeout);
|
|
timeout = null;
|
|
previous = now;
|
|
result = func.apply(context, args);
|
|
} else if (!timeout) {
|
|
timeout = setTimeout(later, remaining);
|
|
}
|
|
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, result;
|
|
return function() {
|
|
var context = this, args = arguments;
|
|
var later = function() {
|
|
timeout = null;
|
|
if (!immediate) result = func.apply(context, args);
|
|
};
|
|
var callNow = immediate && !timeout;
|
|
clearTimeout(timeout);
|
|
timeout = setTimeout(later, wait);
|
|
if (callNow) result = func.apply(context, args);
|
|
return result;
|
|
};
|
|
};
|
|
|
|
// 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;
|
|
memo = func.apply(this, arguments);
|
|
func = null;
|
|
return memo;
|
|
};
|
|
};
|
|
|
|
// 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];
|
|
push.apply(args, arguments);
|
|
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) {
|
|
var values = [];
|
|
for (var key in obj) if (_.has(obj, key)) values.push(obj[key]);
|
|
return values;
|
|
};
|
|
|
|
// Convert an object into a list of `[key, value]` pairs.
|
|
_.pairs = function(obj) {
|
|
var pairs = [];
|
|
for (var key in obj) if (_.has(obj, key)) pairs.push([key, obj[key]]);
|
|
return pairs;
|
|
};
|
|
|
|
// Invert the keys and values of an object. The values must be serializable.
|
|
_.invert = function(obj) {
|
|
var result = {};
|
|
for (var key in obj) if (_.has(obj, key)) result[obj[key]] = key;
|
|
return result;
|
|
};
|
|
|
|
// 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) {
|
|
if (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 copy = {};
|
|
var keys = concat.apply(ArrayProto, slice.call(arguments, 1));
|
|
each(keys, function(key) {
|
|
if (key in obj) copy[key] = obj[key];
|
|
});
|
|
return copy;
|
|
};
|
|
|
|
// Return a copy of the object without the blacklisted properties.
|
|
_.omit = function(obj) {
|
|
var copy = {};
|
|
var keys = concat.apply(ArrayProto, slice.call(arguments, 1));
|
|
for (var key in obj) {
|
|
if (!_.contains(keys, key)) copy[key] = obj[key];
|
|
}
|
|
return copy;
|
|
};
|
|
|
|
// Fill in a given object with default properties.
|
|
_.defaults = function(obj) {
|
|
each(slice.call(arguments, 1), function(source) {
|
|
if (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 for `isEqual`.
|
|
var eq = function(a, b, aStack, bStack) {
|
|
// 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 instanceof _) a = a._wrapped;
|
|
if (b instanceof _) b = b._wrapped;
|
|
// 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 = aStack.length;
|
|
while (length--) {
|
|
// Linear search. Performance is inversely proportional to the number of
|
|
// unique nested structures.
|
|
if (aStack[length] == a) return bStack[length] == b;
|
|
}
|
|
// Add the first object to the stack of traversed objects.
|
|
aStack.push(a);
|
|
bStack.push(b);
|
|
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--) {
|
|
if (!(result = eq(a[size], b[size], aStack, bStack))) break;
|
|
}
|
|
}
|
|
} else {
|
|
// Objects with different constructors are not equivalent, but `Object`s
|
|
// from different frames are.
|
|
var aCtor = a.constructor, bCtor = b.constructor;
|
|
if (aCtor !== bCtor && !(_.isFunction(aCtor) && (aCtor instanceof aCtor) &&
|
|
_.isFunction(bCtor) && (bCtor instanceof bCtor))) {
|
|
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], aStack, bStack))) 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.
|
|
aStack.pop();
|
|
bStack.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);
|
|
};
|
|
|
|
// Add some isType methods: isArguments, isFunction, isString, isNumber, isDate, isRegExp.
|
|
each(['Arguments', 'Function', 'String', 'Number', 'Date', 'RegExp'], function(name) {
|
|
_['is' + name] = function(obj) {
|
|
return toString.call(obj) == '[object ' + name + ']';
|
|
};
|
|
});
|
|
|
|
// Define a fallback version of the method in browsers (ahem, IE), where
|
|
// there isn't any inspectable "Arguments" type.
|
|
if (!_.isArguments(arguments)) {
|
|
_.isArguments = function(obj) {
|
|
return !!(obj && _.has(obj, 'callee'));
|
|
};
|
|
}
|
|
|
|
// Optimize `isFunction` if appropriate.
|
|
if (typeof (/./) !== 'function') {
|
|
_.isFunction = function(obj) {
|
|
return typeof obj === 'function';
|
|
};
|
|
}
|
|
|
|
// Is a given object a finite number?
|
|
_.isFinite = function(obj) {
|
|
return isFinite(obj) && !isNaN(parseFloat(obj));
|
|
};
|
|
|
|
// Is the given value `NaN`? (NaN is the only number which does not equal itself).
|
|
_.isNaN = function(obj) {
|
|
return _.isNumber(obj) && 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 equal to null?
|
|
_.isNull = function(obj) {
|
|
return obj === null;
|
|
};
|
|
|
|
// Is a given variable undefined?
|
|
_.isUndefined = function(obj) {
|
|
return obj === void 0;
|
|
};
|
|
|
|
// Shortcut function for checking if an object has a given property directly
|
|
// on itself (in other words, not on a prototype).
|
|
_.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) {
|
|
var accum = Array(n);
|
|
for (var i = 0; i < n; i++) accum[i] = iterator.call(context, i);
|
|
return accum;
|
|
};
|
|
|
|
// Return a random integer between min and max (inclusive).
|
|
_.random = function(min, max) {
|
|
if (max == null) {
|
|
max = min;
|
|
min = 0;
|
|
}
|
|
return min + Math.floor(Math.random() * (max - min + 1));
|
|
};
|
|
|
|
// List of HTML entities for escaping.
|
|
var entityMap = {
|
|
escape: {
|
|
'&': '&',
|
|
'<': '<',
|
|
'>': '>',
|
|
'"': '"',
|
|
"'": ''',
|
|
'/': '/'
|
|
}
|
|
};
|
|
entityMap.unescape = _.invert(entityMap.escape);
|
|
|
|
// Regexes containing the keys and values listed immediately above.
|
|
var entityRegexes = {
|
|
escape: new RegExp('[' + _.keys(entityMap.escape).join('') + ']', 'g'),
|
|
unescape: new RegExp('(' + _.keys(entityMap.unescape).join('|') + ')', 'g')
|
|
};
|
|
|
|
// Functions for escaping and unescaping strings to/from HTML interpolation.
|
|
_.each(['escape', 'unescape'], function(method) {
|
|
_[method] = function(string) {
|
|
if (string == null) return '';
|
|
return ('' + string).replace(entityRegexes[method], function(match) {
|
|
return entityMap[method][match];
|
|
});
|
|
};
|
|
});
|
|
|
|
// 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.
|
|
_.mixin = function(obj) {
|
|
each(_.functions(obj), function(name){
|
|
var func = _[name] = obj[name];
|
|
_.prototype[name] = function() {
|
|
var args = [this._wrapped];
|
|
push.apply(args, arguments);
|
|
return result.call(this, func.apply(_, args));
|
|
};
|
|
});
|
|
};
|
|
|
|
// 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'
|
|
};
|
|
|
|
var escaper = /\\|'|\r|\n|\t|\u2028|\u2029/g;
|
|
|
|
// 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) {
|
|
var render;
|
|
settings = _.defaults({}, settings, _.templateSettings);
|
|
|
|
// Combine delimiters into one regular expression via alternation.
|
|
var matcher = new RegExp([
|
|
(settings.escape || noMatch).source,
|
|
(settings.interpolate || noMatch).source,
|
|
(settings.evaluate || noMatch).source
|
|
].join('|') + '|$', 'g');
|
|
|
|
// Compile the template source, escaping string literals appropriately.
|
|
var index = 0;
|
|
var source = "__p+='";
|
|
text.replace(matcher, function(match, escape, interpolate, evaluate, offset) {
|
|
source += text.slice(index, offset)
|
|
.replace(escaper, function(match) { return '\\' + escapes[match]; });
|
|
|
|
if (escape) {
|
|
source += "'+\n((__t=(" + escape + "))==null?'':_.escape(__t))+\n'";
|
|
}
|
|
if (interpolate) {
|
|
source += "'+\n((__t=(" + interpolate + "))==null?'':__t)+\n'";
|
|
}
|
|
if (evaluate) {
|
|
source += "';\n" + evaluate + "\n__p+='";
|
|
}
|
|
index = offset + match.length;
|
|
return match;
|
|
});
|
|
source += "';\n";
|
|
|
|
// If a variable is not specified, place data values in local scope.
|
|
if (!settings.variable) source = 'with(obj||{}){\n' + source + '}\n';
|
|
|
|
source = "var __t,__p='',__j=Array.prototype.join," +
|
|
"print=function(){__p+=__j.call(arguments,'');};\n" +
|
|
source + "return __p;\n";
|
|
|
|
try {
|
|
render = new Function(settings.variable || 'obj', '_', source);
|
|
} catch (e) {
|
|
e.source = source;
|
|
throw e;
|
|
}
|
|
|
|
if (data) return render(data, _);
|
|
var template = function(data) {
|
|
return render.call(this, data, _);
|
|
};
|
|
|
|
// Provide the compiled function source as a convenience for 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();
|
|
};
|
|
|
|
// OOP
|
|
// ---------------
|
|
// 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.
|
|
|
|
// Helper function to continue chaining intermediate results.
|
|
var result = function(obj) {
|
|
return this._chain ? _(obj).chain() : obj;
|
|
};
|
|
|
|
// 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];
|
|
_.prototype[name] = function() {
|
|
var obj = this._wrapped;
|
|
method.apply(obj, arguments);
|
|
if ((name == 'shift' || name == 'splice') && obj.length === 0) delete obj[0];
|
|
return result.call(this, obj);
|
|
};
|
|
});
|
|
|
|
// Add all accessor Array functions to the wrapper.
|
|
each(['concat', 'join', 'slice'], function(name) {
|
|
var method = ArrayProto[name];
|
|
_.prototype[name] = function() {
|
|
return result.call(this, method.apply(this._wrapped, arguments));
|
|
};
|
|
});
|
|
|
|
_.extend(_.prototype, {
|
|
|
|
// Start chaining a wrapped Underscore object.
|
|
chain: function() {
|
|
this._chain = true;
|
|
return this;
|
|
},
|
|
|
|
// Extracts the result from a wrapped and chained object.
|
|
value: function() {
|
|
return this._wrapped;
|
|
}
|
|
|
|
});
|
|
|
|
}).call(this);
|