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/**
* Lo-Dash 2.4.1 (Custom Build) <http://lodash.com/>
* Build: `lodash modularize exports="node" -o ./compat/`
* Copyright 2012-2013 The Dojo Foundation <http://dojofoundation.org/>
* Based on Underscore.js 1.5.2 <http://underscorejs.org/LICENSE>
* Copyright 2009-2013 Jeremy Ashkenas, DocumentCloud and Investigative Reporters & Editors
* Available under MIT license <http://lodash.com/license>
*/
var baseUniq = require('../internals/baseUniq'),
createCallback = require('../functions/createCallback');
/**
* Creates a duplicate-value-free version of an array using strict equality
* for comparisons, i.e. `===`. If the array is sorted, providing
* `true` for `isSorted` will use a faster algorithm. If a callback is provided
* each element of `array` is passed through the callback before uniqueness
* is computed. The callback is bound to `thisArg` and invoked with three
* arguments; (value, index, array).
*
* If a property name is provided for `callback` the created "_.pluck" style
* callback will return the property value of the given element.
*
* If an object is provided for `callback` the created "_.where" style callback
* will return `true` for elements that have the properties of the given object,
* else `false`.
*
* @static
* @memberOf _
* @alias unique
* @category Arrays
* @param {Array} array The array to process.
* @param {boolean} [isSorted=false] A flag to indicate that `array` is sorted.
* @param {Function|Object|string} [callback=identity] The function called
* per iteration. If a property name or object is provided it will be used
* to create a "_.pluck" or "_.where" style callback, respectively.
* @param {*} [thisArg] The `this` binding of `callback`.
* @returns {Array} Returns a duplicate-value-free array.
* @example
*
* _.uniq([1, 2, 1, 3, 1]);
* // => [1, 2, 3]
*
* _.uniq([1, 1, 2, 2, 3], true);
* // => [1, 2, 3]
*
* _.uniq(['A', 'b', 'C', 'a', 'B', 'c'], function(letter) { return letter.toLowerCase(); });
* // => ['A', 'b', 'C']
*
* _.uniq([1, 2.5, 3, 1.5, 2, 3.5], function(num) { return this.floor(num); }, Math);
* // => [1, 2.5, 3]
*
* // using "_.pluck" callback shorthand
* _.uniq([{ 'x': 1 }, { 'x': 2 }, { 'x': 1 }], 'x');
* // => [{ 'x': 1 }, { 'x': 2 }]
*/
function uniq(array, isSorted, callback, thisArg) {
// juggle arguments
if (typeof isSorted != 'boolean' && isSorted != null) {
thisArg = callback;
callback = (typeof isSorted != 'function' && thisArg && thisArg[isSorted] === array) ? null : isSorted;
isSorted = false;
}
if (callback != null) {
callback = createCallback(callback, thisArg, 3);
}
return baseUniq(array, isSorted, callback);
}
module.exports = uniq;