36 lines
643 B
TypeScript
36 lines
643 B
TypeScript
// @strictNullChecks: true
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// Type guards involving type parameters produce intersection types
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class C {
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prop: string;
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}
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function f1<T>(x: T) {
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if (x instanceof C) {
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let v1: T = x;
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let v2: C = x;
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x.prop;
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}
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}
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function f2<T>(x: T) {
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if (typeof x === "string") {
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let v1: T = x;
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let v2: string = x;
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x.length;
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}
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}
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// Repro from #13872
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function fun<T>(item: { [P in keyof T]: T[P] }) {
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const strings: string[] = [];
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for (const key in item) {
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const value = item[key];
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if (typeof value === "string") {
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strings.push(value);
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}
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}
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}
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