05f73ca409
* fix: convert js algorithms and data structures * fix: revert some blocks back to blockquote * fix: reverted comparison code block to blockquotes * fix: change js to json Co-Authored-By: Oliver Eyton-Williams <ojeytonwilliams@gmail.com> * fix: convert various section to triple backticks * fix: Make the formatting consistent for comparisons
87 lines
2.4 KiB
Markdown
87 lines
2.4 KiB
Markdown
---
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id: 599a789b454f2bbd91a3ff4d
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title: Practice comparing different values
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challengeType: 1
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videoUrl: 'https://scrimba.com/c/cm8PqCa'
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---
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## Description
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<section id='description'>
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In the last two challenges, we learned about the equality operator (<code>==</code>) and the strict equality operator (<code>===</code>). Let's do a quick review and practice using these operators some more.
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If the values being compared are not of the same type, the equality operator will perform a type conversion, and then evaluate the values. However, the strict equality operator will compare both the data type and value as-is, without converting one type to the other.
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<strong>Examples</strong>
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```js
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3 == '3' // returns true because JavaScript performs type conversion from string to number
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3 === '3' // returns false because the types are different and type conversion is not performed
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```
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<strong>Note</strong><br>In JavaScript, you can determine the type of a variable or a value with the <code>typeof</code> operator, as follows:
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```js
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typeof 3 // returns 'number'
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typeof '3' // returns 'string'
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```
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</section>
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## Instructions
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<section id='instructions'>
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The <code>compareEquality</code> function in the editor compares two values using the <code>equality operator</code>. Modify the function so that it returns "Equal" only when the values are strictly equal.
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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>compareEquality(10, "10")</code> should return "Not Equal"
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testString: assert(compareEquality(10, "10") === "Not Equal", '<code>compareEquality(10, "10")</code> should return "Not Equal"');
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- text: <code>compareEquality("20", 20)</code> should return "Not Equal"
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testString: assert(compareEquality("20", 20) === "Not Equal", '<code>compareEquality("20", 20)</code> should return "Not Equal"');
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- text: You should use the <code>===</code> operator
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testString: assert(code.match(/===/g), 'You should use the <code>===</code> operator');
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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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function compareEquality(a, b) {
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if (a == b) { // Change this line
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return "Equal";
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}
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return "Not Equal";
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}
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// Change this value to test
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compareEquality(10, "10");
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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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function compareEquality(a,b) {
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if (a === b) {
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return "Equal";
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}
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return "Not Equal";
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}
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```
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</section>
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