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/**
* Lo-Dash 2.4.1 (Custom Build) <http://lodash.com/>
* Build: `lodash modularize modern exports="node" -o ./modern/`
* 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'),
identity = require('../utilities/identity');
/**
* Uses a binary search to determine the smallest index at which a value
* should be inserted into a given sorted array in order to maintain the sort
* order of the array. If a callback is provided it will be executed for
* `value` and each element of `array` to compute their sort ranking. The
* callback is bound to `thisArg` and invoked with one argument; (value).
*
* 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 Arrays
* @param {Array} array The array to inspect.
* @param {*} value The value to evaluate.
* @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 {number} Returns the index at which `value` should be inserted
* into `array`.
* @example
*
* _.sortedIndex([20, 30, 50], 40);
* // => 2
*
* // using "_.pluck" callback shorthand
* _.sortedIndex([{ 'x': 20 }, { 'x': 30 }, { 'x': 50 }], { 'x': 40 }, 'x');
* // => 2
*
* var dict = {
* 'wordToNumber': { 'twenty': 20, 'thirty': 30, 'fourty': 40, 'fifty': 50 }
* };
*
* _.sortedIndex(['twenty', 'thirty', 'fifty'], 'fourty', function(word) {
* return dict.wordToNumber[word];
* });
* // => 2
*
* _.sortedIndex(['twenty', 'thirty', 'fifty'], 'fourty', function(word) {
* return this.wordToNumber[word];
* }, dict);
* // => 2
*/
function sortedIndex(array, value, callback, thisArg) {
var low = 0,
high = array ? array.length : low;
// explicitly reference `identity` for better inlining in Firefox
callback = callback ? createCallback(callback, thisArg, 1) : identity;
value = callback(value);
while (low < high) {
var mid = (low + high) >>> 1;
(callback(array[mid]) < value)
? low = mid + 1
: high = mid;
}
return low;
}
module.exports = sortedIndex;