2024-05-06 20:40:05 +00:00
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---
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2024-10-30 17:04:36 +00:00
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date: 20200911
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2024-05-06 20:40:05 +00:00
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id: 6b091d50-aa10-4ba8-a652-43cd5433371e
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title: JavaScript Callbacks
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---
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# Examples
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## setTimeout
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``` javascript
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setTimeout(() => { console.log("This will echo after 2 seconds!"); }, 2000);
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```
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# ES6
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## Best practices
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### Prefer arrow functions as callbacks
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As callbacks, [arrow functions](20201006111349-arrow_functions) have two
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advantages over traditional functions:
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- `this` is lexical and therefore safer to use.
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- Their syntax is more compact. That matters especially in functional
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programming, where there are many higher-order functions and methods
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(functions and methods whose parameters are functions).
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