45 lines
		
	
	
		
			1.3 KiB
		
	
	
	
		
			JavaScript
		
	
	
	
	
	
			
		
		
	
	
			45 lines
		
	
	
		
			1.3 KiB
		
	
	
	
		
			JavaScript
		
	
	
	
	
	
| var baseFindKey = require('./_baseFindKey'),
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|     baseForOwn = require('./_baseForOwn'),
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|     baseIteratee = require('./_baseIteratee');
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| 
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| /**
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|  * This method is like `_.find` except that it returns the key of the first
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|  * element `predicate` returns truthy for instead of the element itself.
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|  *
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|  * @static
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|  * @memberOf _
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|  * @since 1.1.0
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|  * @category Object
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|  * @param {Object} object The object to inspect.
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|  * @param {Function} [predicate=_.identity] The function invoked per iteration.
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|  * @returns {string|undefined} Returns the key of the matched element,
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|  *  else `undefined`.
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|  * @example
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|  *
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|  * var users = {
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|  *   'barney':  { 'age': 36, 'active': true },
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|  *   'fred':    { 'age': 40, 'active': false },
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|  *   'pebbles': { 'age': 1,  'active': true }
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|  * };
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|  *
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|  * _.findKey(users, function(o) { return o.age < 40; });
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|  * // => 'barney' (iteration order is not guaranteed)
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|  *
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|  * // The `_.matches` iteratee shorthand.
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|  * _.findKey(users, { 'age': 1, 'active': true });
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|  * // => 'pebbles'
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|  *
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|  * // The `_.matchesProperty` iteratee shorthand.
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|  * _.findKey(users, ['active', false]);
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|  * // => 'fred'
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|  *
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|  * // The `_.property` iteratee shorthand.
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|  * _.findKey(users, 'active');
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|  * // => 'barney'
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|  */
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| function findKey(object, predicate) {
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|   return baseFindKey(object, baseIteratee(predicate, 3), baseForOwn);
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| }
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| 
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| module.exports = findKey;
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