30 lines
646 B
TypeScript
30 lines
646 B
TypeScript
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// @target: es6
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// repro mostly from https://github.com/Microsoft/TypeScript/issues/25065
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function getProperty2<T, K extends keyof T>(obj: T, key: Extract<K, string>): T[K] {
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return obj[key];
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}
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function getProperty3<T, K extends Extract<keyof T, string>>(obj: T, key: K): T[K] {
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return obj[key];
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}
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const s = Symbol();
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interface StrNum {
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first: string;
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second: number;
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[s]: string;
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}
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const obj: StrNum = {} as any;
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let prop: string;
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// should work
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prop = getProperty2(obj, 'first');
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prop = getProperty3(obj, 'first');
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// Should fail
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prop = getProperty2(obj, s);
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prop = getProperty3(obj, s);
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