mirror of
https://github.com/WordPress/WordPress.git
synced 2024-12-27 03:27:46 +01:00
877f356334
See #45785. Built from https://develop.svn.wordpress.org/trunk@46093 git-svn-id: http://core.svn.wordpress.org/trunk@45905 1a063a9b-81f0-0310-95a4-ce76da25c4cd
1549 lines
52 KiB
JavaScript
1549 lines
52 KiB
JavaScript
// Underscore.js 1.8.3
|
||
// http://underscorejs.org
|
||
// (c) 2009-2015 Jeremy Ashkenas, DocumentCloud and Investigative Reporters & Editors
|
||
// Underscore may be freely distributed under the MIT license.
|
||
|
||
(function() {
|
||
|
||
// Baseline setup
|
||
// --------------
|
||
|
||
// Establish the root object, `window` in the browser, or `exports` on the server.
|
||
var root = this;
|
||
|
||
// Save the previous value of the `_` variable.
|
||
var previousUnderscore = root._;
|
||
|
||
// Save bytes in the minified (but not gzipped) version:
|
||
var ArrayProto = Array.prototype, ObjProto = Object.prototype, FuncProto = Function.prototype;
|
||
|
||
// Create quick reference variables for speed access to core prototypes.
|
||
var
|
||
push = ArrayProto.push,
|
||
slice = ArrayProto.slice,
|
||
toString = ObjProto.toString,
|
||
hasOwnProperty = ObjProto.hasOwnProperty;
|
||
|
||
// All **ECMAScript 5** native function implementations that we hope to use
|
||
// are declared here.
|
||
var
|
||
nativeIsArray = Array.isArray,
|
||
nativeKeys = Object.keys,
|
||
nativeBind = FuncProto.bind,
|
||
nativeCreate = Object.create;
|
||
|
||
// Naked function reference for surrogate-prototype-swapping.
|
||
var Ctor = function(){};
|
||
|
||
// Create a safe reference to the Underscore object for use below.
|
||
var _ = function(obj) {
|
||
if (obj instanceof _) return obj;
|
||
if (!(this instanceof _)) return new _(obj);
|
||
this._wrapped = obj;
|
||
};
|
||
|
||
// Export the Underscore object for **Node.js**, with
|
||
// backwards-compatibility for the old `require()` API. If we're in
|
||
// the browser, add `_` as a global object.
|
||
if (typeof exports !== 'undefined') {
|
||
if (typeof module !== 'undefined' && module.exports) {
|
||
exports = module.exports = _;
|
||
}
|
||
exports._ = _;
|
||
} else {
|
||
root._ = _;
|
||
}
|
||
|
||
// Current version.
|
||
_.VERSION = '1.8.3';
|
||
|
||
// Internal function that returns an efficient (for current engines) version
|
||
// of the passed-in callback, to be repeatedly applied in other Underscore
|
||
// functions.
|
||
var optimizeCb = function(func, context, argCount) {
|
||
if (context === void 0) return func;
|
||
switch (argCount == null ? 3 : argCount) {
|
||
case 1: return function(value) {
|
||
return func.call(context, value);
|
||
};
|
||
case 2: return function(value, other) {
|
||
return func.call(context, value, other);
|
||
};
|
||
case 3: return function(value, index, collection) {
|
||
return func.call(context, value, index, collection);
|
||
};
|
||
case 4: return function(accumulator, value, index, collection) {
|
||
return func.call(context, accumulator, value, index, collection);
|
||
};
|
||
}
|
||
return function() {
|
||
return func.apply(context, arguments);
|
||
};
|
||
};
|
||
|
||
// A mostly-internal function to generate callbacks that can be applied
|
||
// to each element in a collection, returning the desired result — either
|
||
// identity, an arbitrary callback, a property matcher, or a property accessor.
|
||
var cb = function(value, context, argCount) {
|
||
if (value == null) return _.identity;
|
||
if (_.isFunction(value)) return optimizeCb(value, context, argCount);
|
||
if (_.isObject(value)) return _.matcher(value);
|
||
return _.property(value);
|
||
};
|
||
_.iteratee = function(value, context) {
|
||
return cb(value, context, Infinity);
|
||
};
|
||
|
||
// An internal function for creating assigner functions.
|
||
var createAssigner = function(keysFunc, undefinedOnly) {
|
||
return function(obj) {
|
||
var length = arguments.length;
|
||
if (length < 2 || obj == null) return obj;
|
||
for (var index = 1; index < length; index++) {
|
||
var source = arguments[index],
|
||
keys = keysFunc(source),
|
||
l = keys.length;
|
||
for (var i = 0; i < l; i++) {
|
||
var key = keys[i];
|
||
if (!undefinedOnly || obj[key] === void 0) obj[key] = source[key];
|
||
}
|
||
}
|
||
return obj;
|
||
};
|
||
};
|
||
|
||
// An internal function for creating a new object that inherits from another.
|
||
var baseCreate = function(prototype) {
|
||
if (!_.isObject(prototype)) return {};
|
||
if (nativeCreate) return nativeCreate(prototype);
|
||
Ctor.prototype = prototype;
|
||
var result = new Ctor;
|
||
Ctor.prototype = null;
|
||
return result;
|
||
};
|
||
|
||
var property = function(key) {
|
||
return function(obj) {
|
||
return obj == null ? void 0 : obj[key];
|
||
};
|
||
};
|
||
|
||
// Helper for collection methods to determine whether a collection
|
||
// should be iterated as an array or as an object
|
||
// Related: http://people.mozilla.org/~jorendorff/es6-draft.html#sec-tolength
|
||
// Avoids a very nasty iOS 8 JIT bug on ARM-64. #2094
|
||
var MAX_ARRAY_INDEX = Math.pow(2, 53) - 1;
|
||
var getLength = property('length');
|
||
var isArrayLike = function(collection) {
|
||
var length = getLength(collection);
|
||
return typeof length == 'number' && length >= 0 && length <= MAX_ARRAY_INDEX;
|
||
};
|
||
|
||
// Collection Functions
|
||
// --------------------
|
||
|
||
// The cornerstone, an `each` implementation, aka `forEach`.
|
||
// Handles raw objects in addition to array-likes. Treats all
|
||
// sparse array-likes as if they were dense.
|
||
_.each = _.forEach = function(obj, iteratee, context) {
|
||
iteratee = optimizeCb(iteratee, context);
|
||
var i, length;
|
||
if (isArrayLike(obj)) {
|
||
for (i = 0, length = obj.length; i < length; i++) {
|
||
iteratee(obj[i], i, obj);
|
||
}
|
||
} else {
|
||
var keys = _.keys(obj);
|
||
for (i = 0, length = keys.length; i < length; i++) {
|
||
iteratee(obj[keys[i]], keys[i], obj);
|
||
}
|
||
}
|
||
return obj;
|
||
};
|
||
|
||
// Return the results of applying the iteratee to each element.
|
||
_.map = _.collect = function(obj, iteratee, context) {
|
||
iteratee = cb(iteratee, context);
|
||
var keys = !isArrayLike(obj) && _.keys(obj),
|
||
length = (keys || obj).length,
|
||
results = Array(length);
|
||
for (var index = 0; index < length; index++) {
|
||
var currentKey = keys ? keys[index] : index;
|
||
results[index] = iteratee(obj[currentKey], currentKey, obj);
|
||
}
|
||
return results;
|
||
};
|
||
|
||
// Create a reducing function iterating left or right.
|
||
function createReduce(dir) {
|
||
// Optimized iterator function as using arguments.length
|
||
// in the main function will deoptimize the, see #1991.
|
||
function iterator(obj, iteratee, memo, keys, index, length) {
|
||
for (; index >= 0 && index < length; index += dir) {
|
||
var currentKey = keys ? keys[index] : index;
|
||
memo = iteratee(memo, obj[currentKey], currentKey, obj);
|
||
}
|
||
return memo;
|
||
}
|
||
|
||
return function(obj, iteratee, memo, context) {
|
||
iteratee = optimizeCb(iteratee, context, 4);
|
||
var keys = !isArrayLike(obj) && _.keys(obj),
|
||
length = (keys || obj).length,
|
||
index = dir > 0 ? 0 : length - 1;
|
||
// Determine the initial value if none is provided.
|
||
if (arguments.length < 3) {
|
||
memo = obj[keys ? keys[index] : index];
|
||
index += dir;
|
||
}
|
||
return iterator(obj, iteratee, memo, keys, index, length);
|
||
};
|
||
}
|
||
|
||
// **Reduce** builds up a single result from a list of values, aka `inject`,
|
||
// or `foldl`.
|
||
_.reduce = _.foldl = _.inject = createReduce(1);
|
||
|
||
// The right-associative version of reduce, also known as `foldr`.
|
||
_.reduceRight = _.foldr = createReduce(-1);
|
||
|
||
// Return the first value which passes a truth test. Aliased as `detect`.
|
||
_.find = _.detect = function(obj, predicate, context) {
|
||
var key;
|
||
if (isArrayLike(obj)) {
|
||
key = _.findIndex(obj, predicate, context);
|
||
} else {
|
||
key = _.findKey(obj, predicate, context);
|
||
}
|
||
if (key !== void 0 && key !== -1) return obj[key];
|
||
};
|
||
|
||
// Return all the elements that pass a truth test.
|
||
// Aliased as `select`.
|
||
_.filter = _.select = function(obj, predicate, context) {
|
||
var results = [];
|
||
predicate = cb(predicate, context);
|
||
_.each(obj, function(value, index, list) {
|
||
if (predicate(value, index, list)) results.push(value);
|
||
});
|
||
return results;
|
||
};
|
||
|
||
// Return all the elements for which a truth test fails.
|
||
_.reject = function(obj, predicate, context) {
|
||
return _.filter(obj, _.negate(cb(predicate)), context);
|
||
};
|
||
|
||
// Determine whether all of the elements match a truth test.
|
||
// Aliased as `all`.
|
||
_.every = _.all = function(obj, predicate, context) {
|
||
predicate = cb(predicate, context);
|
||
var keys = !isArrayLike(obj) && _.keys(obj),
|
||
length = (keys || obj).length;
|
||
for (var index = 0; index < length; index++) {
|
||
var currentKey = keys ? keys[index] : index;
|
||
if (!predicate(obj[currentKey], currentKey, obj)) return false;
|
||
}
|
||
return true;
|
||
};
|
||
|
||
// Determine if at least one element in the object matches a truth test.
|
||
// Aliased as `any`.
|
||
_.some = _.any = function(obj, predicate, context) {
|
||
predicate = cb(predicate, context);
|
||
var keys = !isArrayLike(obj) && _.keys(obj),
|
||
length = (keys || obj).length;
|
||
for (var index = 0; index < length; index++) {
|
||
var currentKey = keys ? keys[index] : index;
|
||
if (predicate(obj[currentKey], currentKey, obj)) return true;
|
||
}
|
||
return false;
|
||
};
|
||
|
||
// Determine if the array or object contains a given item (using `===`).
|
||
// Aliased as `includes` and `include`.
|
||
_.contains = _.includes = _.include = function(obj, item, fromIndex, guard) {
|
||
if (!isArrayLike(obj)) obj = _.values(obj);
|
||
if (typeof fromIndex != 'number' || guard) fromIndex = 0;
|
||
return _.indexOf(obj, item, fromIndex) >= 0;
|
||
};
|
||
|
||
// Invoke a method (with arguments) on every item in a collection.
|
||
_.invoke = function(obj, method) {
|
||
var args = slice.call(arguments, 2);
|
||
var isFunc = _.isFunction(method);
|
||
return _.map(obj, function(value) {
|
||
var func = isFunc ? method : value[method];
|
||
return func == null ? func : func.apply(value, args);
|
||
});
|
||
};
|
||
|
||
// Convenience version of a common use case of `map`: fetching a property.
|
||
_.pluck = function(obj, key) {
|
||
return _.map(obj, _.property(key));
|
||
};
|
||
|
||
// Convenience version of a common use case of `filter`: selecting only objects
|
||
// containing specific `key:value` pairs.
|
||
_.where = function(obj, attrs) {
|
||
return _.filter(obj, _.matcher(attrs));
|
||
};
|
||
|
||
// Convenience version of a common use case of `find`: getting the first object
|
||
// containing specific `key:value` pairs.
|
||
_.findWhere = function(obj, attrs) {
|
||
return _.find(obj, _.matcher(attrs));
|
||
};
|
||
|
||
// Return the maximum element (or element-based computation).
|
||
_.max = function(obj, iteratee, context) {
|
||
var result = -Infinity, lastComputed = -Infinity,
|
||
value, computed;
|
||
if (iteratee == null && obj != null) {
|
||
obj = isArrayLike(obj) ? obj : _.values(obj);
|
||
for (var i = 0, length = obj.length; i < length; i++) {
|
||
value = obj[i];
|
||
if (value > result) {
|
||
result = value;
|
||
}
|
||
}
|
||
} else {
|
||
iteratee = cb(iteratee, context);
|
||
_.each(obj, function(value, index, list) {
|
||
computed = iteratee(value, index, list);
|
||
if (computed > lastComputed || computed === -Infinity && result === -Infinity) {
|
||
result = value;
|
||
lastComputed = computed;
|
||
}
|
||
});
|
||
}
|
||
return result;
|
||
};
|
||
|
||
// Return the minimum element (or element-based computation).
|
||
_.min = function(obj, iteratee, context) {
|
||
var result = Infinity, lastComputed = Infinity,
|
||
value, computed;
|
||
if (iteratee == null && obj != null) {
|
||
obj = isArrayLike(obj) ? obj : _.values(obj);
|
||
for (var i = 0, length = obj.length; i < length; i++) {
|
||
value = obj[i];
|
||
if (value < result) {
|
||
result = value;
|
||
}
|
||
}
|
||
} else {
|
||
iteratee = cb(iteratee, context);
|
||
_.each(obj, function(value, index, list) {
|
||
computed = iteratee(value, index, list);
|
||
if (computed < lastComputed || computed === Infinity && result === Infinity) {
|
||
result = value;
|
||
lastComputed = computed;
|
||
}
|
||
});
|
||
}
|
||
return result;
|
||
};
|
||
|
||
// Shuffle a collection, using the modern version of the
|
||
// [Fisher-Yates shuffle](http://en.wikipedia.org/wiki/Fisher–Yates_shuffle).
|
||
_.shuffle = function(obj) {
|
||
var set = isArrayLike(obj) ? obj : _.values(obj);
|
||
var length = set.length;
|
||
var shuffled = Array(length);
|
||
for (var index = 0, rand; index < length; index++) {
|
||
rand = _.random(0, index);
|
||
if (rand !== index) shuffled[index] = shuffled[rand];
|
||
shuffled[rand] = set[index];
|
||
}
|
||
return shuffled;
|
||
};
|
||
|
||
// Sample **n** random values from a collection.
|
||
// If **n** is not specified, returns a single random element.
|
||
// The internal `guard` argument allows it to work with `map`.
|
||
_.sample = function(obj, n, guard) {
|
||
if (n == null || guard) {
|
||
if (!isArrayLike(obj)) obj = _.values(obj);
|
||
return obj[_.random(obj.length - 1)];
|
||
}
|
||
return _.shuffle(obj).slice(0, Math.max(0, n));
|
||
};
|
||
|
||
// Sort the object's values by a criterion produced by an iteratee.
|
||
_.sortBy = function(obj, iteratee, context) {
|
||
iteratee = cb(iteratee, context);
|
||
return _.pluck(_.map(obj, function(value, index, list) {
|
||
return {
|
||
value: value,
|
||
index: index,
|
||
criteria: iteratee(value, index, list)
|
||
};
|
||
}).sort(function(left, right) {
|
||
var a = left.criteria;
|
||
var b = right.criteria;
|
||
if (a !== b) {
|
||
if (a > b || a === void 0) return 1;
|
||
if (a < b || b === void 0) return -1;
|
||
}
|
||
return left.index - right.index;
|
||
}), 'value');
|
||
};
|
||
|
||
// An internal function used for aggregate "group by" operations.
|
||
var group = function(behavior) {
|
||
return function(obj, iteratee, context) {
|
||
var result = {};
|
||
iteratee = cb(iteratee, context);
|
||
_.each(obj, function(value, index) {
|
||
var key = iteratee(value, index, obj);
|
||
behavior(result, value, key);
|
||
});
|
||
return result;
|
||
};
|
||
};
|
||
|
||
// Groups the object's values by a criterion. Pass either a string attribute
|
||
// to group by, or a function that returns the criterion.
|
||
_.groupBy = group(function(result, value, key) {
|
||
if (_.has(result, key)) result[key].push(value); else result[key] = [value];
|
||
});
|
||
|
||
// Indexes the object's values by a criterion, similar to `groupBy`, but for
|
||
// when you know that your index values will be unique.
|
||
_.indexBy = group(function(result, value, key) {
|
||
result[key] = value;
|
||
});
|
||
|
||
// Counts instances of an object that group by a certain criterion. Pass
|
||
// either a string attribute to count by, or a function that returns the
|
||
// criterion.
|
||
_.countBy = group(function(result, value, key) {
|
||
if (_.has(result, key)) result[key]++; else result[key] = 1;
|
||
});
|
||
|
||
// Safely create a real, live array from anything iterable.
|
||
_.toArray = function(obj) {
|
||
if (!obj) return [];
|
||
if (_.isArray(obj)) return slice.call(obj);
|
||
if (isArrayLike(obj)) return _.map(obj, _.identity);
|
||
return _.values(obj);
|
||
};
|
||
|
||
// Return the number of elements in an object.
|
||
_.size = function(obj) {
|
||
if (obj == null) return 0;
|
||
return isArrayLike(obj) ? obj.length : _.keys(obj).length;
|
||
};
|
||
|
||
// Split a collection into two arrays: one whose elements all satisfy the given
|
||
// predicate, and one whose elements all do not satisfy the predicate.
|
||
_.partition = function(obj, predicate, context) {
|
||
predicate = cb(predicate, context);
|
||
var pass = [], fail = [];
|
||
_.each(obj, function(value, key, obj) {
|
||
(predicate(value, key, obj) ? pass : fail).push(value);
|
||
});
|
||
return [pass, fail];
|
||
};
|
||
|
||
// Array Functions
|
||
// ---------------
|
||
|
||
// Get the first element of an array. Passing **n** will return the first N
|
||
// values in the array. Aliased as `head` and `take`. The **guard** check
|
||
// allows it to work with `_.map`.
|
||
_.first = _.head = _.take = function(array, n, guard) {
|
||
if (array == null) return void 0;
|
||
if (n == null || guard) return array[0];
|
||
return _.initial(array, array.length - n);
|
||
};
|
||
|
||
// 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.
|
||
_.initial = function(array, n, guard) {
|
||
return slice.call(array, 0, Math.max(0, array.length - (n == null || guard ? 1 : n)));
|
||
};
|
||
|
||
// Get the last element of an array. Passing **n** will return the last N
|
||
// values in the array.
|
||
_.last = function(array, n, guard) {
|
||
if (array == null) return void 0;
|
||
if (n == null || guard) return array[array.length - 1];
|
||
return _.rest(array, Math.max(0, array.length - n));
|
||
};
|
||
|
||
// 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.
|
||
_.rest = _.tail = _.drop = function(array, n, guard) {
|
||
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, strict, startIndex) {
|
||
var output = [], idx = 0;
|
||
for (var i = startIndex || 0, length = getLength(input); i < length; i++) {
|
||
var value = input[i];
|
||
if (isArrayLike(value) && (_.isArray(value) || _.isArguments(value))) {
|
||
//flatten current level of array or arguments object
|
||
if (!shallow) value = flatten(value, shallow, strict);
|
||
var j = 0, len = value.length;
|
||
output.length += len;
|
||
while (j < len) {
|
||
output[idx++] = value[j++];
|
||
}
|
||
} else if (!strict) {
|
||
output[idx++] = value;
|
||
}
|
||
}
|
||
return output;
|
||
};
|
||
|
||
// Flatten out an array, either recursively (by default), or just one level.
|
||
_.flatten = function(array, shallow) {
|
||
return flatten(array, shallow, false);
|
||
};
|
||
|
||
// Return a version of the array that does not contain the specified value(s).
|
||
_.without = function(array) {
|
||
return _.difference(array, slice.call(arguments, 1));
|
||
};
|
||
|
||
// 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, iteratee, context) {
|
||
if (!_.isBoolean(isSorted)) {
|
||
context = iteratee;
|
||
iteratee = isSorted;
|
||
isSorted = false;
|
||
}
|
||
if (iteratee != null) iteratee = cb(iteratee, context);
|
||
var result = [];
|
||
var seen = [];
|
||
for (var i = 0, length = getLength(array); i < length; i++) {
|
||
var value = array[i],
|
||
computed = iteratee ? iteratee(value, i, array) : value;
|
||
if (isSorted) {
|
||
if (!i || seen !== computed) result.push(value);
|
||
seen = computed;
|
||
} else if (iteratee) {
|
||
if (!_.contains(seen, computed)) {
|
||
seen.push(computed);
|
||
result.push(value);
|
||
}
|
||
} else if (!_.contains(result, value)) {
|
||
result.push(value);
|
||
}
|
||
}
|
||
return result;
|
||
};
|
||
|
||
// Produce an array that contains the union: each distinct element from all of
|
||
// the passed-in arrays.
|
||
_.union = function() {
|
||
return _.uniq(flatten(arguments, true, true));
|
||
};
|
||
|
||
// Produce an array that contains every item shared between all the
|
||
// passed-in arrays.
|
||
_.intersection = function(array) {
|
||
var result = [];
|
||
var argsLength = arguments.length;
|
||
for (var i = 0, length = getLength(array); i < length; i++) {
|
||
var item = array[i];
|
||
if (_.contains(result, item)) continue;
|
||
for (var j = 1; j < argsLength; j++) {
|
||
if (!_.contains(arguments[j], item)) break;
|
||
}
|
||
if (j === argsLength) result.push(item);
|
||
}
|
||
return result;
|
||
};
|
||
|
||
// 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 = flatten(arguments, true, true, 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() {
|
||
return _.unzip(arguments);
|
||
};
|
||
|
||
// Complement of _.zip. Unzip accepts an array of arrays and groups
|
||
// each array's elements on shared indices
|
||
_.unzip = function(array) {
|
||
var length = array && _.max(array, getLength).length || 0;
|
||
var result = Array(length);
|
||
|
||
for (var index = 0; index < length; index++) {
|
||
result[index] = _.pluck(array, index);
|
||
}
|
||
return result;
|
||
};
|
||
|
||
// 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) {
|
||
var result = {};
|
||
for (var i = 0, length = getLength(list); i < length; i++) {
|
||
if (values) {
|
||
result[list[i]] = values[i];
|
||
} else {
|
||
result[list[i][0]] = list[i][1];
|
||
}
|
||
}
|
||
return result;
|
||
};
|
||
|
||
// Generator function to create the findIndex and findLastIndex functions
|
||
function createPredicateIndexFinder(dir) {
|
||
return function(array, predicate, context) {
|
||
predicate = cb(predicate, context);
|
||
var length = getLength(array);
|
||
var index = dir > 0 ? 0 : length - 1;
|
||
for (; index >= 0 && index < length; index += dir) {
|
||
if (predicate(array[index], index, array)) return index;
|
||
}
|
||
return -1;
|
||
};
|
||
}
|
||
|
||
// Returns the first index on an array-like that passes a predicate test
|
||
_.findIndex = createPredicateIndexFinder(1);
|
||
_.findLastIndex = createPredicateIndexFinder(-1);
|
||
|
||
// Use a comparator function to figure out the smallest index at which
|
||
// an object should be inserted so as to maintain order. Uses binary search.
|
||
_.sortedIndex = function(array, obj, iteratee, context) {
|
||
iteratee = cb(iteratee, context, 1);
|
||
var value = iteratee(obj);
|
||
var low = 0, high = getLength(array);
|
||
while (low < high) {
|
||
var mid = Math.floor((low + high) / 2);
|
||
if (iteratee(array[mid]) < value) low = mid + 1; else high = mid;
|
||
}
|
||
return low;
|
||
};
|
||
|
||
// Generator function to create the indexOf and lastIndexOf functions
|
||
function createIndexFinder(dir, predicateFind, sortedIndex) {
|
||
return function(array, item, idx) {
|
||
var i = 0, length = getLength(array);
|
||
if (typeof idx == 'number') {
|
||
if (dir > 0) {
|
||
i = idx >= 0 ? idx : Math.max(idx + length, i);
|
||
} else {
|
||
length = idx >= 0 ? Math.min(idx + 1, length) : idx + length + 1;
|
||
}
|
||
} else if (sortedIndex && idx && length) {
|
||
idx = sortedIndex(array, item);
|
||
return array[idx] === item ? idx : -1;
|
||
}
|
||
if (item !== item) {
|
||
idx = predicateFind(slice.call(array, i, length), _.isNaN);
|
||
return idx >= 0 ? idx + i : -1;
|
||
}
|
||
for (idx = dir > 0 ? i : length - 1; idx >= 0 && idx < length; idx += dir) {
|
||
if (array[idx] === item) return idx;
|
||
}
|
||
return -1;
|
||
};
|
||
}
|
||
|
||
// Return the position of the first occurrence of an item in an array,
|
||
// or -1 if the item is not included in the array.
|
||
// If the array is large and already in sort order, pass `true`
|
||
// for **isSorted** to use binary search.
|
||
_.indexOf = createIndexFinder(1, _.findIndex, _.sortedIndex);
|
||
_.lastIndexOf = createIndexFinder(-1, _.findLastIndex);
|
||
|
||
// 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 (stop == null) {
|
||
stop = start || 0;
|
||
start = 0;
|
||
}
|
||
step = step || 1;
|
||
|
||
var length = Math.max(Math.ceil((stop - start) / step), 0);
|
||
var range = Array(length);
|
||
|
||
for (var idx = 0; idx < length; idx++, start += step) {
|
||
range[idx] = start;
|
||
}
|
||
|
||
return range;
|
||
};
|
||
|
||
// Function (ahem) Functions
|
||
// ------------------
|
||
|
||
// Determines whether to execute a function as a constructor
|
||
// or a normal function with the provided arguments
|
||
var executeBound = function(sourceFunc, boundFunc, context, callingContext, args) {
|
||
if (!(callingContext instanceof boundFunc)) return sourceFunc.apply(context, args);
|
||
var self = baseCreate(sourceFunc.prototype);
|
||
var result = sourceFunc.apply(self, args);
|
||
if (_.isObject(result)) return result;
|
||
return self;
|
||
};
|
||
|
||
// 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 (nativeBind && func.bind === nativeBind) return nativeBind.apply(func, slice.call(arguments, 1));
|
||
if (!_.isFunction(func)) throw new TypeError('Bind must be called on a function');
|
||
var args = slice.call(arguments, 2);
|
||
var bound = function() {
|
||
return executeBound(func, bound, context, this, args.concat(slice.call(arguments)));
|
||
};
|
||
return bound;
|
||
};
|
||
|
||
// 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);
|
||
var bound = function() {
|
||
var position = 0, length = boundArgs.length;
|
||
var args = Array(length);
|
||
for (var i = 0; i < length; i++) {
|
||
args[i] = boundArgs[i] === _ ? arguments[position++] : boundArgs[i];
|
||
}
|
||
while (position < arguments.length) args.push(arguments[position++]);
|
||
return executeBound(func, bound, this, this, args);
|
||
};
|
||
return bound;
|
||
};
|
||
|
||
// 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 i, length = arguments.length, key;
|
||
if (length <= 1) throw new Error('bindAll must be passed function names');
|
||
for (i = 1; i < length; i++) {
|
||
key = arguments[i];
|
||
obj[key] = _.bind(obj[key], obj);
|
||
}
|
||
return obj;
|
||
};
|
||
|
||
// Memoize an expensive function by storing its results.
|
||
_.memoize = function(func, hasher) {
|
||
var memoize = function(key) {
|
||
var cache = memoize.cache;
|
||
var address = '' + (hasher ? hasher.apply(this, arguments) : key);
|
||
if (!_.has(cache, address)) cache[address] = func.apply(this, arguments);
|
||
return cache[address];
|
||
};
|
||
memoize.cache = {};
|
||
return memoize;
|
||
};
|
||
|
||
// 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 = _.partial(_.delay, _, 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;
|
||
if (!options) options = {};
|
||
var later = function() {
|
||
previous = options.leading === false ? 0 : _.now();
|
||
timeout = null;
|
||
result = func.apply(context, args);
|
||
if (!timeout) 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 || remaining > wait) {
|
||
if (timeout) {
|
||
clearTimeout(timeout);
|
||
timeout = null;
|
||
}
|
||
previous = now;
|
||
result = func.apply(context, args);
|
||
if (!timeout) 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 && last >= 0) {
|
||
timeout = setTimeout(later, wait - last);
|
||
} else {
|
||
timeout = null;
|
||
if (!immediate) {
|
||
result = func.apply(context, args);
|
||
if (!timeout) 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 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 negated version of the passed-in predicate.
|
||
_.negate = function(predicate) {
|
||
return function() {
|
||
return !predicate.apply(this, arguments);
|
||
};
|
||
};
|
||
|
||
// 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 args = arguments;
|
||
var start = args.length - 1;
|
||
return function() {
|
||
var i = start;
|
||
var result = args[start].apply(this, arguments);
|
||
while (i--) result = args[i].call(this, result);
|
||
return result;
|
||
};
|
||
};
|
||
|
||
// Returns a function that will only be executed on and after the Nth call.
|
||
_.after = function(times, func) {
|
||
return function() {
|
||
if (--times < 1) {
|
||
return func.apply(this, arguments);
|
||
}
|
||
};
|
||
};
|
||
|
||
// Returns a function that will only be executed up to (but not including) the Nth call.
|
||
_.before = function(times, func) {
|
||
var memo;
|
||
return function() {
|
||
if (--times > 0) {
|
||
memo = func.apply(this, arguments);
|
||
}
|
||
if (times <= 1) func = null;
|
||
return memo;
|
||
};
|
||
};
|
||
|
||
// Returns a function that will be executed at most one time, no matter how
|
||
// often you call it. Useful for lazy initialization.
|
||
_.once = _.partial(_.before, 2);
|
||
|
||
// Object Functions
|
||
// ----------------
|
||
|
||
// Keys in IE < 9 that won't be iterated by `for key in ...` and thus missed.
|
||
var hasEnumBug = !{toString: null}.propertyIsEnumerable('toString');
|
||
var nonEnumerableProps = ['valueOf', 'isPrototypeOf', 'toString',
|
||
'propertyIsEnumerable', 'hasOwnProperty', 'toLocaleString'];
|
||
|
||
function collectNonEnumProps(obj, keys) {
|
||
var nonEnumIdx = nonEnumerableProps.length;
|
||
var constructor = obj.constructor;
|
||
var proto = (_.isFunction(constructor) && constructor.prototype) || ObjProto;
|
||
|
||
// Constructor is a special case.
|
||
var prop = 'constructor';
|
||
if (_.has(obj, prop) && !_.contains(keys, prop)) keys.push(prop);
|
||
|
||
while (nonEnumIdx--) {
|
||
prop = nonEnumerableProps[nonEnumIdx];
|
||
if (prop in obj && obj[prop] !== proto[prop] && !_.contains(keys, prop)) {
|
||
keys.push(prop);
|
||
}
|
||
}
|
||
}
|
||
|
||
// Retrieve the names of an object's own 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);
|
||
// Ahem, IE < 9.
|
||
if (hasEnumBug) collectNonEnumProps(obj, keys);
|
||
return keys;
|
||
};
|
||
|
||
// Retrieve all the property names of an object.
|
||
_.allKeys = function(obj) {
|
||
if (!_.isObject(obj)) return [];
|
||
var keys = [];
|
||
for (var key in obj) keys.push(key);
|
||
// Ahem, IE < 9.
|
||
if (hasEnumBug) collectNonEnumProps(obj, keys);
|
||
return keys;
|
||
};
|
||
|
||
// Retrieve the values of an object's properties.
|
||
_.values = function(obj) {
|
||
var keys = _.keys(obj);
|
||
var length = keys.length;
|
||
var values = Array(length);
|
||
for (var i = 0; i < length; i++) {
|
||
values[i] = obj[keys[i]];
|
||
}
|
||
return values;
|
||
};
|
||
|
||
// Returns the results of applying the iteratee to each element of the object
|
||
// In contrast to _.map it returns an object
|
||
_.mapObject = function(obj, iteratee, context) {
|
||
iteratee = cb(iteratee, context);
|
||
var keys = _.keys(obj),
|
||
length = keys.length,
|
||
results = {},
|
||
currentKey;
|
||
for (var index = 0; index < length; index++) {
|
||
currentKey = keys[index];
|
||
results[currentKey] = iteratee(obj[currentKey], currentKey, obj);
|
||
}
|
||
return results;
|
||
};
|
||
|
||
// Convert an object into a list of `[key, value]` pairs.
|
||
_.pairs = function(obj) {
|
||
var keys = _.keys(obj);
|
||
var length = keys.length;
|
||
var pairs = 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 = createAssigner(_.allKeys);
|
||
|
||
// Assigns a given object with all the own properties in the passed-in object(s)
|
||
// (https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Object/assign)
|
||
_.extendOwn = _.assign = createAssigner(_.keys);
|
||
|
||
// Returns the first key on an object that passes a predicate test
|
||
_.findKey = function(obj, predicate, context) {
|
||
predicate = cb(predicate, context);
|
||
var keys = _.keys(obj), key;
|
||
for (var i = 0, length = keys.length; i < length; i++) {
|
||
key = keys[i];
|
||
if (predicate(obj[key], key, obj)) return key;
|
||
}
|
||
};
|
||
|
||
// Return a copy of the object only containing the whitelisted properties.
|
||
_.pick = function(object, oiteratee, context) {
|
||
var result = {}, obj = object, iteratee, keys;
|
||
if (obj == null) return result;
|
||
if (_.isFunction(oiteratee)) {
|
||
keys = _.allKeys(obj);
|
||
iteratee = optimizeCb(oiteratee, context);
|
||
} else {
|
||
keys = flatten(arguments, false, false, 1);
|
||
iteratee = function(value, key, obj) { return key in obj; };
|
||
obj = Object(obj);
|
||
}
|
||
for (var i = 0, length = keys.length; i < length; i++) {
|
||
var key = keys[i];
|
||
var value = obj[key];
|
||
if (iteratee(value, key, obj)) result[key] = value;
|
||
}
|
||
return result;
|
||
};
|
||
|
||
// Return a copy of the object without the blacklisted properties.
|
||
_.omit = function(obj, iteratee, context) {
|
||
if (_.isFunction(iteratee)) {
|
||
iteratee = _.negate(iteratee);
|
||
} else {
|
||
var keys = _.map(flatten(arguments, false, false, 1), String);
|
||
iteratee = function(value, key) {
|
||
return !_.contains(keys, key);
|
||
};
|
||
}
|
||
return _.pick(obj, iteratee, context);
|
||
};
|
||
|
||
// Fill in a given object with default properties.
|
||
_.defaults = createAssigner(_.allKeys, true);
|
||
|
||
// Creates an object that inherits from the given prototype object.
|
||
// If additional properties are provided then they will be added to the
|
||
// created object.
|
||
_.create = function(prototype, props) {
|
||
var result = baseCreate(prototype);
|
||
if (props) _.extendOwn(result, props);
|
||
return result;
|
||
};
|
||
|
||
// 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;
|
||
};
|
||
|
||
// Returns whether an object has a given set of `key:value` pairs.
|
||
_.isMatch = function(object, attrs) {
|
||
var keys = _.keys(attrs), length = keys.length;
|
||
if (object == null) return !length;
|
||
var obj = Object(object);
|
||
for (var i = 0; i < length; i++) {
|
||
var key = keys[i];
|
||
if (attrs[key] !== obj[key] || !(key in obj)) return false;
|
||
}
|
||
return true;
|
||
};
|
||
|
||
|
||
// 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, regular expressions, dates, and booleans are compared by value.
|
||
case '[object RegExp]':
|
||
// RegExps are coerced to strings for comparison (Note: '' + /a/i === '/a/i')
|
||
case '[object String]':
|
||
// Primitives and their corresponding object wrappers are equivalent; thus, `"5"` is
|
||
// equivalent to `new String("5")`.
|
||
return '' + a === '' + b;
|
||
case '[object Number]':
|
||
// `NaN`s are equivalent, but non-reflexive.
|
||
// Object(NaN) is equivalent to NaN
|
||
if (+a !== +a) return +b !== +b;
|
||
// An `egal` comparison is performed for other numeric values.
|
||
return +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;
|
||
}
|
||
|
||
var areArrays = className === '[object Array]';
|
||
if (!areArrays) {
|
||
if (typeof a != 'object' || typeof b != 'object') return false;
|
||
|
||
// Objects with different constructors are not equivalent, but `Object`s or `Array`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;
|
||
}
|
||
}
|
||
// Assume equality for cyclic structures. The algorithm for detecting cyclic
|
||
// structures is adapted from ES 5.1 section 15.12.3, abstract operation `JO`.
|
||
|
||
// Initializing stack of traversed objects.
|
||
// It's done here since we only need them for objects and arrays comparison.
|
||
aStack = aStack || [];
|
||
bStack = bStack || [];
|
||
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);
|
||
|
||
// Recursively compare objects and arrays.
|
||
if (areArrays) {
|
||
// Compare array lengths to determine if a deep comparison is necessary.
|
||
length = a.length;
|
||
if (length !== b.length) return false;
|
||
// Deep compare the contents, ignoring non-numeric properties.
|
||
while (length--) {
|
||
if (!eq(a[length], b[length], aStack, bStack)) return false;
|
||
}
|
||
} else {
|
||
// Deep compare objects.
|
||
var keys = _.keys(a), key;
|
||
length = keys.length;
|
||
// Ensure that both objects contain the same number of properties before comparing deep equality.
|
||
if (_.keys(b).length !== length) return false;
|
||
while (length--) {
|
||
// Deep compare each member
|
||
key = keys[length];
|
||
if (!(_.has(b, key) && eq(a[key], b[key], aStack, bStack))) return false;
|
||
}
|
||
}
|
||
// Remove the first object from the stack of traversed objects.
|
||
aStack.pop();
|
||
bStack.pop();
|
||
return true;
|
||
};
|
||
|
||
// 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 (isArrayLike(obj) && (_.isArray(obj) || _.isString(obj) || _.isArguments(obj))) return obj.length === 0;
|
||
return _.keys(obj).length === 0;
|
||
};
|
||
|
||
// 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) {
|
||
var type = typeof obj;
|
||
return type === 'function' || type === 'object' && !!obj;
|
||
};
|
||
|
||
// Add some isType methods: isArguments, isFunction, isString, isNumber, isDate, isRegExp, isError.
|
||
_.each(['Arguments', 'Function', 'String', 'Number', 'Date', 'RegExp', 'Error'], function(name) {
|
||
_['is' + name] = function(obj) {
|
||
return toString.call(obj) === '[object ' + name + ']';
|
||
};
|
||
});
|
||
|
||
// Define a fallback version of the method in browsers (ahem, IE < 9), where
|
||
// there isn't any inspectable "Arguments" type.
|
||
if (!_.isArguments(arguments)) {
|
||
_.isArguments = function(obj) {
|
||
return _.has(obj, 'callee');
|
||
};
|
||
}
|
||
|
||
// Optimize `isFunction` if appropriate. Work around some typeof bugs in old v8,
|
||
// IE 11 (#1621), and in Safari 8 (#1929).
|
||
if (typeof /./ != 'function' && typeof Int8Array != 'object') {
|
||
_.isFunction = function(obj) {
|
||
return typeof obj == 'function' || false;
|
||
};
|
||
}
|
||
|
||
// 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 obj != null && 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 iteratees.
|
||
_.identity = function(value) {
|
||
return value;
|
||
};
|
||
|
||
// Predicate-generating functions. Often useful outside of Underscore.
|
||
_.constant = function(value) {
|
||
return function() {
|
||
return value;
|
||
};
|
||
};
|
||
|
||
_.noop = function(){};
|
||
|
||
_.property = property;
|
||
|
||
// Generates a function for a given object that returns a given property.
|
||
_.propertyOf = function(obj) {
|
||
return obj == null ? function(){} : function(key) {
|
||
return obj[key];
|
||
};
|
||
};
|
||
|
||
// Returns a predicate for checking whether an object has a given set of
|
||
// `key:value` pairs.
|
||
_.matcher = _.matches = function(attrs) {
|
||
attrs = _.extendOwn({}, attrs);
|
||
return function(obj) {
|
||
return _.isMatch(obj, attrs);
|
||
};
|
||
};
|
||
|
||
// Run a function **n** times.
|
||
_.times = function(n, iteratee, context) {
|
||
var accum = Array(Math.max(0, n));
|
||
iteratee = optimizeCb(iteratee, context, 1);
|
||
for (var i = 0; i < n; i++) accum[i] = iteratee(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 escapeMap = {
|
||
'&': '&',
|
||
'<': '<',
|
||
'>': '>',
|
||
'"': '"',
|
||
"'": ''',
|
||
'`': '`'
|
||
};
|
||
var unescapeMap = _.invert(escapeMap);
|
||
|
||
// Functions for escaping and unescaping strings to/from HTML interpolation.
|
||
var createEscaper = function(map) {
|
||
var escaper = function(match) {
|
||
return map[match];
|
||
};
|
||
// Regexes for identifying a key that needs to be escaped
|
||
var source = '(?:' + _.keys(map).join('|') + ')';
|
||
var testRegexp = RegExp(source);
|
||
var replaceRegexp = RegExp(source, 'g');
|
||
return function(string) {
|
||
string = string == null ? '' : '' + string;
|
||
return testRegexp.test(string) ? string.replace(replaceRegexp, escaper) : string;
|
||
};
|
||
};
|
||
_.escape = createEscaper(escapeMap);
|
||
_.unescape = createEscaper(unescapeMap);
|
||
|
||
// 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, fallback) {
|
||
var value = object == null ? void 0 : object[property];
|
||
if (value === void 0) {
|
||
value = fallback;
|
||
}
|
||
return _.isFunction(value) ? value.call(object) : value;
|
||
};
|
||
|
||
// 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',
|
||
'\u2028': 'u2028',
|
||
'\u2029': 'u2029'
|
||
};
|
||
|
||
var escaper = /\\|'|\r|\n|\u2028|\u2029/g;
|
||
|
||
var escapeChar = function(match) {
|
||
return '\\' + escapes[match];
|
||
};
|
||
|
||
// JavaScript micro-templating, similar to John Resig's implementation.
|
||
// Underscore templating handles arbitrary delimiters, preserves whitespace,
|
||
// and correctly escapes quotes within interpolated code.
|
||
// NB: `oldSettings` only exists for backwards compatibility.
|
||
_.template = function(text, settings, oldSettings) {
|
||
if (!settings && oldSettings) settings = oldSettings;
|
||
settings = _.defaults({}, settings, _.templateSettings);
|
||
|
||
// Combine delimiters into one regular expression via alternation.
|
||
var matcher = 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, escapeChar);
|
||
index = offset + match.length;
|
||
|
||
if (escape) {
|
||
source += "'+\n((__t=(" + escape + "))==null?'':_.escape(__t))+\n'";
|
||
} else if (interpolate) {
|
||
source += "'+\n((__t=(" + interpolate + "))==null?'':__t)+\n'";
|
||
} else if (evaluate) {
|
||
source += "';\n" + evaluate + "\n__p+='";
|
||
}
|
||
|
||
// Adobe VMs need the match returned to produce the correct offest.
|
||
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 {
|
||
var render = new Function(settings.variable || 'obj', '_', source);
|
||
} catch (e) {
|
||
e.source = source;
|
||
throw e;
|
||
}
|
||
|
||
var template = function(data) {
|
||
return render.call(this, data, _);
|
||
};
|
||
|
||
// Provide the compiled source as a convenience for precompilation.
|
||
var argument = settings.variable || 'obj';
|
||
template.source = 'function(' + argument + '){\n' + source + '}';
|
||
|
||
return template;
|
||
};
|
||
|
||
// Add a "chain" function. Start chaining a wrapped Underscore object.
|
||
_.chain = function(obj) {
|
||
var instance = _(obj);
|
||
instance._chain = true;
|
||
return instance;
|
||
};
|
||
|
||
// 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(instance, obj) {
|
||
return instance._chain ? _(obj).chain() : obj;
|
||
};
|
||
|
||
// 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(this, func.apply(_, args));
|
||
};
|
||
});
|
||
};
|
||
|
||
// 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(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(this, method.apply(this._wrapped, arguments));
|
||
};
|
||
});
|
||
|
||
// Extracts the result from a wrapped and chained object.
|
||
_.prototype.value = function() {
|
||
return this._wrapped;
|
||
};
|
||
|
||
// Provide unwrapping proxy for some methods used in engine operations
|
||
// such as arithmetic and JSON stringification.
|
||
_.prototype.valueOf = _.prototype.toJSON = _.prototype.value;
|
||
|
||
_.prototype.toString = 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));
|