68 lines
2.4 KiB
Markdown
68 lines
2.4 KiB
Markdown
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---
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id: 587d7b7c367417b2b2512b1b
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title: Use the delete Keyword to Remove Object Properties
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challengeType: 1
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---
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## Description
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<section id='description'>
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Now you know what objects are and their basic features and advantages. In short, they are key-value stores which provide a flexible, intuitive way to structure data, <strong><em>and</em></strong>, they provide very fast lookup time. Throughout the rest of these challenges, we will describe several common operations you can perform on objects so you can become comfortable applying these useful data structures in your programs.
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In earlier challenges, we have both added to and modified an object's key-value pairs. Here we will see how we can <em>remove</em> a key-value pair from an object.
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Let's revisit our <code>foods</code> object example one last time. If we wanted to remove the <code>apples</code> key, we can remove it by using the <code>delete</code> keyword like this:
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<blockquote>delete foods.apples;</blockquote>
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</section>
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## Instructions
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<section id='instructions'>
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Use the delete keyword to remove the <code>oranges</code>, <code>plums</code>, and <code>strawberries</code> keys from the <code>foods</code> object.
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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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- text: 'The <code>foods</code> object only has three keys: <code>apples</code>, <code>grapes</code>, and <code>bananas</code>'
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testString: 'assert(!foods.hasOwnProperty("oranges") && !foods.hasOwnProperty("plums") && !foods.hasOwnProperty("strawberries") && Object.keys(foods).length === 3, "The <code>foods</code> object only has three keys: <code>apples</code>, <code>grapes</code>, and <code>bananas</code>");'
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- text: 'The <code>oranges</code>, <code>plums</code>, and <code>strawberries</code> keys are removed using <code>delete</code>'
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testString: 'assert(code.search(/oranges:/) !== -1 && code.search(/plums:/) !== -1 && code.search(/strawberries:/) !== -1, "The <code>oranges</code>, <code>plums</code>, and <code>strawberries</code> keys are removed using <code>delete</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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let foods = {
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apples: 25,
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oranges: 32,
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plums: 28,
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bananas: 13,
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grapes: 35,
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strawberries: 27
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};
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// change code below this line
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// change code above this line
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console.log(foods);
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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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// solution required
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```
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</section>
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