ee1e8abd87
* feat(tools): add seed/solution restore script * chore(curriculum): remove empty sections' markers * chore(curriculum): add seed + solution to Chinese * chore: remove old formatter * fix: update getChallenges parse translated challenges separately, without reference to the source * chore(curriculum): add dashedName to English * chore(curriculum): add dashedName to Chinese * refactor: remove unused challenge property 'name' * fix: relax dashedName requirement * fix: stray tag Remove stray `pre` tag from challenge file. Signed-off-by: nhcarrigan <nhcarrigan@gmail.com> Co-authored-by: nhcarrigan <nhcarrigan@gmail.com>
78 lines
1.6 KiB
Markdown
78 lines
1.6 KiB
Markdown
---
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id: 56bbb991ad1ed5201cd392ce
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title: Manipulate Arrays With unshift()
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challengeType: 1
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videoUrl: 'https://scrimba.com/c/ckNDESv'
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forumTopicId: 18239
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dashedName: manipulate-arrays-with-unshift
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---
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# --description--
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Not only can you `shift` elements off of the beginning of an array, you can also `unshift` elements to the beginning of an array i.e. add elements in front of the array.
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`.unshift()` works exactly like `.push()`, but instead of adding the element at the end of the array, `unshift()` adds the element at the beginning of the array.
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Example:
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```js
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var ourArray = ["Stimpson", "J", "cat"];
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ourArray.shift(); // ourArray now equals ["J", "cat"]
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ourArray.unshift("Happy");
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// ourArray now equals ["Happy", "J", "cat"]
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```
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# --instructions--
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Add `["Paul",35]` to the beginning of the `myArray` variable using `unshift()`.
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# --hints--
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`myArray` should now have \[["Paul", 35], ["dog", 3]].
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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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typeof d[0] === 'object' &&
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d[0][0] == 'Paul' &&
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d[0][1] === 35 &&
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d[1][0] != undefined &&
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d[1][0] == 'dog' &&
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d[1][1] != undefined &&
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d[1][1] == 3
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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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})(myArray)
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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);})(myArray);
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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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myArray.shift();
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// Only change code below this line
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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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myArray.shift();
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myArray.unshift(["Paul", 35]);
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```
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