79 lines
2.0 KiB
Markdown
79 lines
2.0 KiB
Markdown
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---
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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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forumTopicId: 301174
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dashedName: practice-comparing-different-values
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---
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# --description--
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In the last two challenges, we learned about the equality operator (`==`) and the strict equality operator (`===`). 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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**Examples**
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`3 == '3'` returns `true` because JavaScript performs type conversion from string to number. `3 === '3'` returns false because the types are different and type conversion is not performed.
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**Note:** In JavaScript, you can determine the type of a variable or a value with the `typeof` operator, as follows:
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```js
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typeof 3
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typeof '3'
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```
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`typeof 3` returns the string `number`, and `typeof '3'` returns the string `string`.
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# --instructions--
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The `compareEquality` function in the editor compares two values using the equality operator. Modify the function so that it returns the string `Equal` only when the values are strictly equal.
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# --hints--
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`compareEquality(10, "10")` should return the string `Not Equal`
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```js
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assert(compareEquality(10, '10') === 'Not Equal');
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```
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`compareEquality("20", 20)` should return the string `Not Equal`
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```js
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assert(compareEquality('20', 20) === 'Not Equal');
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```
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You should use the `===` operator
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```js
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assert(code.match(/===/g));
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```
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# --seed--
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## --seed-contents--
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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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compareEquality(10, "10");
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```
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# --solutions--
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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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