79d9012432
* fix(curriculum): tests quotes * fix(curriculum): fill seed-teardown * fix(curriculum): fix tests and remove unneeded seed-teardown
115 lines
2.6 KiB
Markdown
115 lines
2.6 KiB
Markdown
---
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id: 56533eb9ac21ba0edf2244cd
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title: Accessing Nested Arrays
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challengeType: 1
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guideUrl: 'https://www.freecodecamp.org/guide/certificates/access-array-data-with-indexes'
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---
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## Description
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<section id='description'>
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As we have seen in earlier examples, objects can contain both nested objects and nested arrays. Similar to accessing nested objects, Array bracket notation can be chained to access nested arrays.
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Here is an example of how to access a nested array:
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<blockquote>var ourPets = [<br> {<br> animalType: "cat",<br> names: [<br> "Meowzer",<br> "Fluffy",<br> "Kit-Cat"<br> ]<br> },<br> {<br> animalType: "dog",<br> names: [<br> "Spot",<br> "Bowser",<br> "Frankie"<br> ]<br> }<br>];<br>ourPets[0].names[1]; // "Fluffy"<br>ourPets[1].names[0]; // "Spot"</blockquote>
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</section>
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## Instructions
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<section id='instructions'>
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Retrieve the second tree from the variable <code>myPlants</code> using object dot and array bracket notation.
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</section>
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## Tests
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<section id='tests'>
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```yml
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tests:
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- text: <code>secondTree</code> should equal "pine"
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testString: assert(secondTree === "pine", '<code>secondTree</code> should equal "pine"');
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- text: Use dot and bracket notation to access <code>myPlants</code>
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testString: assert(/=\s*myPlants\[1\].list\[1\]/.test(code), 'Use dot and bracket notation to access <code>myPlants</code>');
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```
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</section>
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## Challenge Seed
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<section id='challengeSeed'>
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<div id='js-seed'>
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```js
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// Setup
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var myPlants = [
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{
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type: "flowers",
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list: [
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"rose",
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"tulip",
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"dandelion"
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]
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},
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{
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type: "trees",
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list: [
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"fir",
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"pine",
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"birch"
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]
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}
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];
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// Only change code below this line
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var secondTree = ""; // Change this line
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```
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</div>
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### After Test
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<div id='js-teardown'>
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```js
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(function(x) {
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if(typeof x != 'undefined') {
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return "secondTree = " + x;
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}
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return "secondTree is undefined";
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})(secondTree);
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```
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</div>
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</section>
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## Solution
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<section id='solution'>
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```js
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var myPlants = [
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{
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type: "flowers",
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list: [
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"rose",
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"tulip",
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"dandelion"
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]
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},
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{
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type: "trees",
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list: [
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"fir",
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"pine",
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"birch"
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]
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}
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];
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// Only change code below this line
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var secondTree = myPlants[1].list[1];
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```
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</section>
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