2018-09-30 23:01:58 +01:00
										 
									 
								 
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								id: 56bbb991ad1ed5201cd392cd
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								title: Manipulate Arrays With shift()
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								challengeType: 1
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											2019-02-14 12:24:02 -05:00
										 
									 
								 
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								videoUrl: 'https://scrimba.com/c/cRbVETW'
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											2019-07-31 11:32:23 -07:00
										 
									 
								 
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								forumTopicId: 18238
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											2021-01-13 03:31:00 +01:00
										 
									 
								 
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								dashedName: manipulate-arrays-with-shift
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											2018-09-30 23:01:58 +01:00
										 
									 
								 
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								---
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											2020-11-27 19:02:05 +01:00
										 
									 
								 
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								# --description--
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								`pop()` always removes the last element of an array. What if you want to remove the first?
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								That's where `.shift()` comes in. It works just like `.pop()`, except it removes the first element instead of the last.
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								Example:
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								```js
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								var ourArray = ["Stimpson", "J", ["cat"]];
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								var removedFromOurArray = ourArray.shift();
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								```
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											2021-03-02 16:12:12 -08:00
										 
									 
								 
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								`removedFromOurArray` would have a value of the string `Stimpson`, and `ourArray` would have `["J", ["cat"]]`.
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								# --instructions--
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								Use the `.shift()` function to remove the first item from `myArray`, assigning the "shifted off" value to `removedFromMyArray`.
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								# --hints--
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								`myArray` should now equal `[["dog", 3]]`.
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											2020-11-27 19:02:05 +01:00
										 
									 
								 
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								```js
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								assert(
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								  (function (d) {
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								    if (d[0][0] == 'dog' && d[0][1] === 3 && d[1] == undefined) {
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								      return true;
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								    } else {
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								      return false;
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								    }
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								  })(myArray)
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								);
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								```
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								`removedFromMyArray` should contain `["John", 23]`.
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								```js
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								assert(
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								  (function (d) {
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								    if (
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								      d[0] == 'John' &&
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								      d[1] === 23 &&
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								      typeof removedFromMyArray === 'object'
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								    ) {
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								      return true;
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								    } else {
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								      return false;
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								    }
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								  })(removedFromMyArray)
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								);
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								```
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								# --seed--
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								## --after-user-code--
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								```js
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								(function(y, z){return 'myArray = ' + JSON.stringify(y) + ' & removedFromMyArray = ' + JSON.stringify(z);})(myArray, removedFromMyArray);
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								```
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								## --seed-contents--
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								```js
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								// Setup
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								var myArray = [["John", 23], ["dog", 3]];
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								// Only change code below this line
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								var removedFromMyArray;
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								```
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								# --solutions--
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								```js
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								var myArray = [["John", 23], ["dog", 3]];
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											2020-03-02 23:18:30 -08:00
										 
									 
								 
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								// Only change code below this line
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								var removedFromMyArray = myArray.shift();
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								```
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