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/**
* Lo-Dash 2.4.1 (Custom Build) <http://lodash.com/>
* Build: `lodash modularize underscore exports="node" -o ./underscore/`
* 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 createCallback = require('../functions/createCallback'),
forEach = require('./forEach'),
forOwn = require('../objects/forOwn');
/**
* Retrieves the maximum value of a collection. If the collection is empty or
* falsey `-Infinity` is returned. If a callback is provided it will be executed
* for each value in the collection to generate the criterion by which the value
* is ranked. The callback is bound to `thisArg` and invoked with three
* arguments; (value, index, collection).
*
* 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 _
* @category Collections
* @param {Array|Object|string} collection The collection to iterate over.
* @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 {*} Returns the maximum value.
* @example
*
* _.max([4, 2, 8, 6]);
* // => 8
*
* var characters = [
* { 'name': 'barney', 'age': 36 },
* { 'name': 'fred', 'age': 40 }
* ];
*
* _.max(characters, function(chr) { return chr.age; });
* // => { 'name': 'fred', 'age': 40 };
*
* // using "_.pluck" callback shorthand
* _.max(characters, 'age');
* // => { 'name': 'fred', 'age': 40 };
*/
function max(collection, callback, thisArg) {
var computed = -Infinity,
result = computed;
// allows working with functions like `_.map` without using
// their `index` argument as a callback
if (typeof callback != 'function' && thisArg && thisArg[callback] === collection) {
callback = null;
}
var index = -1,
length = collection ? collection.length : 0;
if (callback == null && typeof length == 'number') {
while (++index < length) {
var value = collection[index];
if (value > result) {
result = value;
}
}
} else {
callback = createCallback(callback, thisArg, 3);
forEach(collection, function(value, index, collection) {
var current = callback(value, index, collection);
if (current > computed) {
computed = current;
result = value;
}
});
}
return result;
}
module.exports = max;