44 lines
729 B
TypeScript
44 lines
729 B
TypeScript
//// [controlFlowForInStatement2.ts]
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const keywordA = 'a';
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const keywordB = 'b';
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type A = { [keywordA]: number };
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type B = { [keywordB]: string };
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declare const c: A | B;
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if ('a' in c) {
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c; // narrowed to `A`
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}
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if (keywordA in c) {
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c; // also narrowed to `A`
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}
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let stringB: string = 'b';
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if ((stringB as 'b') in c) {
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c; // narrowed to `B`
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}
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if ((stringB as ('a' | 'b')) in c) {
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c; // not narrowed
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}
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//// [controlFlowForInStatement2.js]
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var keywordA = 'a';
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var keywordB = 'b';
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if ('a' in c) {
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c; // narrowed to `A`
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}
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if (keywordA in c) {
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c; // also narrowed to `A`
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}
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var stringB = 'b';
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if (stringB in c) {
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c; // narrowed to `B`
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}
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if (stringB in c) {
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c; // not narrowed
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}
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