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40 lines
887 B
Markdown
40 lines
887 B
Markdown
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---
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id: 19822398-201e-426a-86f0-48ef5a09acda
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title: JavaScript Booleans
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---
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# Syntax
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``` javascript
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console.log(3 > 2)
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console.log(3 < 2)
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```
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Strings can also be compared
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``` javascript
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console.log("Aardvark" < "Zoroaster")
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```
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Uppercase characters are always less than lower case characters, so "Z"
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\< "a". Non alphabetic characters are less than alphabetic characters
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``` javascript
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console.log("Zebra" < "aardvark")
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console.log("!" < "aardvark")
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console.log("!" < "Zebra")
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console.log("3" < "Zebra")
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console.log("!" < "3")
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```
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## Empty values
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There are two special empty values, null & undefined that denote the
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absence of any meaningful value. They can be used interchangeably and
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are an [accident of JavaScripts
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design](https://medium.com/@stephenthecurt/a-brief-history-of-null-and-undefined-in-javascript-c283caab662e).
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``` javascript
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console.log(null == undefined);
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```
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