1344 lines
44 KiB
JavaScript
1344 lines
44 KiB
JavaScript
// Underscore.js 1.6.0
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// http://underscorejs.org
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// (c) 2009-2014 Jeremy Ashkenas, DocumentCloud and Investigative Reporters & Editors
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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 `exports` 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
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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 = '1.6.0';
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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 obj;
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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, length = obj.length; i < length; 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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var keys = _.keys(obj);
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for (var i = 0, length = keys.length; i < length; i++) {
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if (iterator.call(context, obj[keys[i]], keys[i], obj) === breaker) return;
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}
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}
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return obj;
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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.push(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, predicate, context) {
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var result;
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any(obj, function(value, index, list) {
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if (predicate.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, predicate, 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(predicate, context);
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each(obj, function(value, index, list) {
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if (predicate.call(context, value, index, list)) results.push(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, predicate, context) {
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return _.filter(obj, function(value, index, list) {
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return !predicate.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, predicate, context) {
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predicate || (predicate = _.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(predicate, context);
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each(obj, function(value, index, list) {
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if (!(result = result && predicate.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, predicate, context) {
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predicate || (predicate = _.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(predicate, context);
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each(obj, function(value, index, list) {
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if (result || (result = predicate.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, _.property(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) {
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return _.filter(obj, _.matches(attrs));
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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 _.find(obj, _.matches(attrs));
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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 [WebKit Bug 80797](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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var result = -Infinity, lastComputed = -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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if (computed > lastComputed) {
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result = value;
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lastComputed = computed;
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}
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});
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return result;
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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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var result = Infinity, lastComputed = 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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if (computed < lastComputed) {
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result = value;
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lastComputed = computed;
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}
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});
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return result;
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};
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// Shuffle an array, using the modern version of the
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// [Fisher-Yates shuffle](http://en.wikipedia.org/wiki/Fisher–Yates_shuffle).
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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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// Sample **n** random values from a collection.
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// If **n** is not specified, returns a single random element.
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// The internal `guard` argument allows it to work with `map`.
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_.sample = function(obj, n, guard) {
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if (n == null || guard) {
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if (obj.length !== +obj.length) obj = _.values(obj);
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return obj[_.random(obj.length - 1)];
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}
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return _.shuffle(obj).slice(0, Math.max(0, n));
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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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if (value == null) return _.identity;
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if (_.isFunction(value)) return value;
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return _.property(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, iterator, context) {
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iterator = lookupIterator(iterator);
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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;
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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(behavior) {
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return function(obj, iterator, context) {
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var result = {};
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iterator = lookupIterator(iterator);
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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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};
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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 = group(function(result, key, value) {
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_.has(result, key) ? result[key].push(value) : result[key] = [value];
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});
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// Indexes the object's values by a criterion, similar to `groupBy`, but for
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// when you know that your index values will be unique.
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_.indexBy = group(function(result, key, value) {
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result[key] = value;
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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 = group(function(result, key) {
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_.has(result, key) ? result[key]++ : result[key] = 1;
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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 = 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 create a real, live array from anything iterable.
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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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if ((n == null) || guard) return array[0];
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if (n < 0) return [];
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return slice.call(array, 0, n);
|
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};
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// Returns everything but the last entry of the array. Especially useful on
|
||
// the arguments object. Passing **n** will return all the values in
|
||
// 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) {
|
||
if (array == null) return void 0;
|
||
if ((n == null) || guard) return array[array.length - 1];
|
||
return slice.call(array, Math.max(array.length - n, 0));
|
||
};
|
||
|
||
// Returns everything but the first entry of the array. Aliased as `tail` and `drop`.
|
||
// Especially useful on the arguments object. Passing an **n** will return
|
||
// the rest N values in the array. The **guard**
|
||
// 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);
|
||
};
|
||
|
||
// Trim out all falsy values from an array.
|
||
_.compact = function(array) {
|
||
return _.filter(array, _.identity);
|
||
};
|
||
|
||
// Internal implementation of a recursive `flatten` function.
|
||
var flatten = function(input, shallow, output) {
|
||
if (shallow && _.every(input, _.isArray)) {
|
||
return concat.apply(output, input);
|
||
}
|
||
each(input, function(value) {
|
||
if (_.isArray(value) || _.isArguments(value)) {
|
||
shallow ? push.apply(output, value) : flatten(value, shallow, output);
|
||
} else {
|
||
output.push(value);
|
||
}
|
||
});
|
||
return output;
|
||
};
|
||
|
||
// Flatten out an array, either recursively (by default), or just one level.
|
||
_.flatten = function(array, shallow) {
|
||
return flatten(array, shallow, []);
|
||
};
|
||
|
||
// Return a version of the array that does not contain the specified value(s).
|
||
_.without = function(array) {
|
||
return _.difference(array, slice.call(arguments, 1));
|
||
};
|
||
|
||
// Split an array into two arrays: one whose elements all satisfy the given
|
||
// predicate, and one whose elements all do not satisfy the predicate.
|
||
_.partition = function(array, predicate) {
|
||
var pass = [], fail = [];
|
||
each(array, function(elem) {
|
||
(predicate(elem) ? pass : fail).push(elem);
|
||
});
|
||
return [pass, fail];
|
||
};
|
||
|
||
// Produce a duplicate-free version of the array. If the array has already
|
||
// been sorted, you have the option of using a faster algorithm.
|
||
// Aliased as `unique`.
|
||
_.uniq = _.unique = function(array, isSorted, iterator, context) {
|
||
if (_.isFunction(isSorted)) {
|
||
context = iterator;
|
||
iterator = isSorted;
|
||
isSorted = false;
|
||
}
|
||
var initial = iterator ? _.map(array, iterator, context) : array;
|
||
var results = [];
|
||
var seen = [];
|
||
each(initial, function(value, index) {
|
||
if (isSorted ? (!index || seen[seen.length - 1] !== value) : !_.contains(seen, value)) {
|
||
seen.push(value);
|
||
results.push(array[index]);
|
||
}
|
||
});
|
||
return results;
|
||
};
|
||
|
||
// Produce an array that contains the union: each distinct element from all of
|
||
// the passed-in arrays.
|
||
_.union = function() {
|
||
return _.uniq(_.flatten(arguments, true));
|
||
};
|
||
|
||
// Produce an array that contains every item shared between all the
|
||
// passed-in arrays.
|
||
_.intersection = function(array) {
|
||
var rest = slice.call(arguments, 1);
|
||
return _.filter(_.uniq(array), function(item) {
|
||
return _.every(rest, function(other) {
|
||
return _.contains(other, item);
|
||
});
|
||
});
|
||
};
|
||
|
||
// Take the difference between one array and a number of other arrays.
|
||
// Only the elements present in just the first array will remain.
|
||
_.difference = function(array) {
|
||
var rest = concat.apply(ArrayProto, slice.call(arguments, 1));
|
||
return _.filter(array, function(value){ return !_.contains(rest, value); });
|
||
};
|
||
|
||
// Zip together multiple lists into a single array -- elements that share
|
||
// an index go together.
|
||
_.zip = function() {
|
||
var length = _.max(_.pluck(arguments, 'length').concat(0));
|
||
var results = new Array(length);
|
||
for (var i = 0; i < length; i++) {
|
||
results[i] = _.pluck(arguments, '' + 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, length = list.length; i < length; 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, length = array.length;
|
||
if (isSorted) {
|
||
if (typeof isSorted == 'number') {
|
||
i = (isSorted < 0 ? Math.max(0, length + 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 < length; 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 length = Math.max(Math.ceil((stop - start) / step), 0);
|
||
var idx = 0;
|
||
var range = new Array(length);
|
||
|
||
while(idx < length) {
|
||
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). Delegates to **ECMAScript 5**'s native `Function.bind` if
|
||
// available.
|
||
_.bind = function(func, context) {
|
||
var args, bound;
|
||
if (nativeBind && func.bind === 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;
|
||
ctor.prototype = null;
|
||
var result = func.apply(self, args.concat(slice.call(arguments)));
|
||
if (Object(result) === result) return result;
|
||
return self;
|
||
};
|
||
};
|
||
|
||
// Partially apply a function by creating a version that has had some of its
|
||
// arguments pre-filled, without changing its dynamic `this` context. _ acts
|
||
// as a placeholder, allowing any combination of arguments to be pre-filled.
|
||
_.partial = function(func) {
|
||
var boundArgs = slice.call(arguments, 1);
|
||
return function() {
|
||
var position = 0;
|
||
var args = boundArgs.slice();
|
||
for (var i = 0, length = args.length; i < length; i++) {
|
||
if (args[i] === _) args[i] = arguments[position++];
|
||
}
|
||
while (position < arguments.length) args.push(arguments[position++]);
|
||
return func.apply(this, args);
|
||
};
|
||
};
|
||
|
||
// Bind a number of an object's methods to that object. Remaining arguments
|
||
// are the method names to be bound. 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) throw new Error('bindAll must be passed function names');
|
||
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. Normally, the throttled function will run
|
||
// as much as it can, without ever going more than once per `wait` duration;
|
||
// but if you'd like to disable the execution on the leading edge, pass
|
||
// `{leading: false}`. To disable execution on the trailing edge, ditto.
|
||
_.throttle = function(func, wait, options) {
|
||
var context, args, result;
|
||
var timeout = null;
|
||
var previous = 0;
|
||
options || (options = {});
|
||
var later = function() {
|
||
previous = options.leading === false ? 0 : _.now();
|
||
timeout = null;
|
||
result = func.apply(context, args);
|
||
context = args = null;
|
||
};
|
||
return function() {
|
||
var now = _.now();
|
||
if (!previous && options.leading === false) previous = now;
|
||
var remaining = wait - (now - previous);
|
||
context = this;
|
||
args = arguments;
|
||
if (remaining <= 0) {
|
||
clearTimeout(timeout);
|
||
timeout = null;
|
||
previous = now;
|
||
result = func.apply(context, args);
|
||
context = args = null;
|
||
} else if (!timeout && options.trailing !== false) {
|
||
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, args, context, timestamp, result;
|
||
|
||
var later = function() {
|
||
var last = _.now() - timestamp;
|
||
if (last < wait) {
|
||
timeout = setTimeout(later, wait - last);
|
||
} else {
|
||
timeout = null;
|
||
if (!immediate) {
|
||
result = func.apply(context, args);
|
||
context = args = null;
|
||
}
|
||
}
|
||
};
|
||
|
||
return function() {
|
||
context = this;
|
||
args = arguments;
|
||
timestamp = _.now();
|
||
var callNow = immediate && !timeout;
|
||
if (!timeout) {
|
||
timeout = setTimeout(later, wait);
|
||
}
|
||
if (callNow) {
|
||
result = func.apply(context, args);
|
||
context = args = null;
|
||
}
|
||
|
||
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 _.partial(wrapper, func);
|
||
};
|
||
|
||
// 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) {
|
||
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 = function(obj) {
|
||
if (!_.isObject(obj)) return [];
|
||
if (nativeKeys) return nativeKeys(obj);
|
||
var keys = [];
|
||
for (var key in obj) if (_.has(obj, key)) keys.push(key);
|
||
return keys;
|
||
};
|
||
|
||
// Retrieve the values of an object's properties.
|
||
_.values = function(obj) {
|
||
var keys = _.keys(obj);
|
||
var length = keys.length;
|
||
var values = new Array(length);
|
||
for (var i = 0; i < length; i++) {
|
||
values[i] = obj[keys[i]];
|
||
}
|
||
return values;
|
||
};
|
||
|
||
// Convert an object into a list of `[key, value]` pairs.
|
||
_.pairs = function(obj) {
|
||
var keys = _.keys(obj);
|
||
var length = keys.length;
|
||
var pairs = new Array(length);
|
||
for (var i = 0; i < length; i++) {
|
||
pairs[i] = [keys[i], obj[keys[i]]];
|
||
}
|
||
return pairs;
|
||
};
|
||
|
||
// Invert the keys and values of an object. The values must be serializable.
|
||
_.invert = function(obj) {
|
||
var result = {};
|
||
var keys = _.keys(obj);
|
||
for (var i = 0, length = keys.length; i < length; i++) {
|
||
result[obj[keys[i]]] = keys[i];
|
||
}
|
||
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] === void 0) 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;
|
||
}
|
||
// 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))
|
||
&& ('constructor' in a && 'constructor' in b)) {
|
||
return false;
|
||
}
|
||
// 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 {
|
||
// 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;
|
||
};
|
||
|
||
_.constant = function(value) {
|
||
return function () {
|
||
return value;
|
||
};
|
||
};
|
||
|
||
_.property = function(key) {
|
||
return function(obj) {
|
||
return obj[key];
|
||
};
|
||
};
|
||
|
||
// Returns a predicate for checking whether an object has a given set of `key:value` pairs.
|
||
_.matches = function(attrs) {
|
||
return function(obj) {
|
||
if (obj === attrs) return true; //avoid comparing an object to itself.
|
||
for (var key in attrs) {
|
||
if (attrs[key] !== obj[key])
|
||
return false;
|
||
}
|
||
return true;
|
||
}
|
||
};
|
||
|
||
// Run a function **n** times.
|
||
_.times = function(n, iterator, context) {
|
||
var accum = Array(Math.max(0, 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));
|
||
};
|
||
|
||
// A (possibly faster) way to get the current timestamp as an integer.
|
||
_.now = Date.now || function() { return new Date().getTime(); };
|
||
|
||
// 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 with the
|
||
// `object` as context; otherwise, return it.
|
||
_.result = function(object, property) {
|
||
if (object == null) return void 0;
|
||
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;
|
||
}
|
||
|
||
});
|
||
|
||
// AMD registration happens at the end for compatibility with AMD loaders
|
||
// that may not enforce next-turn semantics on modules. Even though general
|
||
// practice for AMD registration is to be anonymous, underscore registers
|
||
// as a named module because, like jQuery, it is a base library that is
|
||
// popular enough to be bundled in a third party lib, but not be part of
|
||
// an AMD load request. Those cases could generate an error when an
|
||
// anonymous define() is called outside of a loader request.
|
||
if (typeof define === 'function' && define.amd) {
|
||
define('underscore', [], function() {
|
||
return _;
|
||
});
|
||
}
|
||
}).call(this);
|