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								---
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								id: a6e40f1041b06c996f7b2406
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								title: Finders Keepers
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								challengeType: 5
							 
						 
					
						
							
								
									
										
										
										
											2019-07-31 11:32:23 -07:00 
										
									 
								 
							 
							
								
									
										 
									 
								
							 
							
								 
							 
							
							
								forumTopicId: 16016
							 
						 
					
						
							
								
									
										
										
										
											2021-01-13 03:31:00 +01:00 
										
									 
								 
							 
							
								
									
										 
									 
								
							 
							
								 
							 
							
							
								dashedName: finders-keepers
							 
						 
					
						
							
								
									
										
										
										
											2018-09-30 23:01:58 +01:00 
										
									 
								 
							 
							
								
							 
							
								 
							 
							
							
								---
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								
							 
						 
					
						
							
								
									
										
										
										
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								# --description--
 
							 
						 
					
						
							
								
									
										
										
										
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								Create a function that looks through an array `arr`  and returns the first element in it that passes a 'truth test'. This means that given an element `x` , the 'truth test' is passed if `func(x)`  is `true` . If no element passes the test, return `undefined` .
							 
						 
					
						
							
								
									
										
										
										
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								# --hints--
 
							 
						 
					
						
							
								
									
										
										
										
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								`findElement([1, 3, 5, 8, 9, 10], function(num) { return num % 2 === 0; })`  should return `8` .
							 
						 
					
						
							
								
									
										
										
										
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								```js
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								assert.strictEqual(
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								  findElement([1, 3, 5, 8, 9, 10], function (num) {
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								    return num % 2 === 0;
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								  }),
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								  8
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								);
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								```
							 
						 
					
						
							
								
									
										
										
										
											2018-09-30 23:01:58 +01:00 
										
									 
								 
							 
							
								
							 
							
								 
							 
							
							
								
							 
						 
					
						
							
								
									
										
										
										
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								`findElement([1, 3, 5, 9], function(num) { return num % 2 === 0; })`  should return `undefined` .
							 
						 
					
						
							
								
									
										
										
										
											2018-09-30 23:01:58 +01:00 
										
									 
								 
							 
							
								
							 
							
								 
							 
							
							
								
							 
						 
					
						
							
								
									
										
										
										
											2020-11-27 19:02:05 +01:00 
										
									 
								 
							 
							
								
									
										 
									 
								
							 
							
								 
							 
							
							
								```js
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								assert.strictEqual(
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								  findElement([1, 3, 5, 9], function (num) {
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								    return num % 2 === 0;
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								  }),
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								  undefined
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								);
							 
						 
					
						
							
								
									
										
										
										
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								```
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								
							 
						 
					
						
							
								
									
										
										
										
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								# --seed--
 
							 
						 
					
						
							
								
									
										
										
										
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								## --seed-contents--
 
							 
						 
					
						
							
								
									
										
										
										
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								```js
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								function findElement(arr, func) {
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								  let num = 0;
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								  return num;
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								}
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								findElement([1, 2, 3, 4], num => num % 2 === 0);
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								```
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								
							 
						 
					
						
							
								
									
										
										
										
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								# --solutions--
 
							 
						 
					
						
							
								
									
										
										
										
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								```js
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								function findElement(arr, func) {
							 
						 
					
						
							
								
									
										
										
										
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								  return arr.filter(func)[0];
							 
						 
					
						
							
								
									
										
										
										
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								}
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								findElement([1, 2, 3, 4], num => num % 2 === 0);
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								```