41 lines
829 B
Plaintext
41 lines
829 B
Plaintext
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/**
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Create a union of the given object's values, and optionally specify which keys to get the values from.
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Please upvote [this issue](https://github.com/microsoft/TypeScript/issues/31438) if you want to have this type as a built-in in TypeScript.
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@example
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```
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// data.json
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{
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'foo': 1,
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'bar': 2,
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'biz': 3
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}
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// main.ts
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import {ValueOf} from 'type-fest';
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import data = require('./data.json');
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export function getData(name: string): ValueOf<typeof data> {
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return data[name];
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}
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export function onlyBar(name: string): ValueOf<typeof data, 'bar'> {
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return data[name];
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}
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// file.ts
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import {getData, onlyBar} from './main';
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getData('foo');
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//=> 1
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onlyBar('foo');
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//=> TypeError ...
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onlyBar('bar');
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//=> 2
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```
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*/
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export type ValueOf<ObjectType, ValueType extends keyof ObjectType = keyof ObjectType> = ObjectType[ValueType];
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