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38 lines
620 B
Markdown
38 lines
620 B
Markdown
---
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id: 03f42b69-8321-443f-9d1d-fb7814999dd7
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title: JavaScript Async Functions
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---
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# Introduction
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Async Functions[^1] is a new feature implemented in
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[ES2017](20201026104538-es2017) to handle
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[promises](20200911154351-promises).
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# Syntax
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## Fulfilling a promise
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``` javascript
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async function asyncFunc() {
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return 123;
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}
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asyncFunc().then((x) => console.log(x));
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// 123
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```
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## Rejecting a promise
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``` javascript
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async function asyncFunc() {
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throw new Error("Problem!");
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}
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asyncFunc().catch((err) => console.log(err));
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// Error: Problem!
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```
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# Footnotes
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[^1]: <https://github.com/tc39/ecmascript-asyncawait>
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