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								---
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								id: 56bbb991ad1ed5201cd392cd
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								title: Manipulate Arrays With shift()
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								challengeType: 1
							 
						 
					
						
							
								
									
										
										
										
											2018-10-10 16:20:40 -04:00 
										
									 
								 
							 
							
								
									
										 
								
							 
							
								 
							
							
								videoUrl: ''
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								localeTitle: Manipular matrices con cambio ()
							 
						 
					
						
							
								
									
										
										
										
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								---
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								## Description
  
						 
					
						
							
								
									
										
										
										
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								< section  id = "description" >  < code > pop()< / code >  siempre elimina el último elemento de una matriz. ¿Qué pasa si quieres eliminar el primero? Ahí es donde < code > .shift()< / code >  en < code > .shift()< / code >  . Funciona igual que < code > .pop()< / code >  , excepto que elimina el primer elemento en lugar del último. < / section >  
						 
					
						
							
								
									
										
										
										
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								## Instructions
  
						 
					
						
							
								
									
										
										
										
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								< section  id = "instructions" >  Use la función < code > .shift()< / code >  para eliminar el primer elemento de < code > myArray< / code >  , asignando el valor " desviado"  a < code > removedFromMyArray< / code >  . < / section >  
						 
					
						
							
								
									
										
										
										
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								## Tests
  
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								< section  id = 'tests' >  
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								```yml
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								tests:
							 
						 
					
						
							
								
									
										
										
										
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								  -  text: '< code > myArray</ code >  ahora debe ser igual a < code > [[" dog" , 3]]</ code >  .'
							 
						 
					
						
							
								
									
										
										
										
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								    testString: 'assert((function(d){if(d[0][0] == "dog" & &  d[0][1] === 3 & &  d[1] == undefined){return true;}else{return false;}})(myArray), "< code > myArray< / code >  should now equal < code > [["dog", 3]]< / code > .");'
							 
						 
					
						
							
								
									
										
										
										
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								  -  text: '< code > removedFromMyArray</ code >  debe contener < code > [" John" , 23]</ code >  .'
							 
						 
					
						
							
								
									
										
										
										
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								    testString: 'assert((function(d){if(d[0] == "John" & &  d[1] === 23 & &  typeof removedFromMyArray === "object"){return true;}else{return false;}})(removedFromMyArray), "< code > removedFromMyArray< / code >  should contain < code > ["John", 23]< / code > .");'
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								```
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								< / section >  
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								## Challenge Seed
  
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								< section  id = 'challengeSeed' >  
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								< div  id = 'js-seed' >  
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								```js
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								// Example
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								var ourArray = ["Stimpson", "J", ["cat"]];
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								var removedFromOurArray = ourArray.shift();
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								// removedFromOurArray now equals "Stimpson" and ourArray now equals ["J", ["cat"]].
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								// Setup
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								var myArray = [["John", 23], ["dog", 3]];
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								// Only change code below this line.
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								var removedFromMyArray;
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								```
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								< / div >  
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								### After Test
  
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								< div  id = 'js-teardown' >  
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								```js
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								console.info('after the test');
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								```
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								< / div >  
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								< / section >  
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								## Solution
  
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								< section  id = 'solution' >  
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								```js
							 
						 
					
						
							
								
									
										
										
										
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								// solution required
							 
						 
					
						
							
								
									
										
										
										
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								```
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								< / section >