22 lines
679 B
TypeScript
22 lines
679 B
TypeScript
//// [subtypingWithOptionalProperties.ts]
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// subtyping is not transitive due to optional properties but the subtyping algorithm assumes it is for the 99% case
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// returns { s?: number; }
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function f<T>(a: T) {
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var b: { s?: number } = a;
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return b;
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}
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var r = f({ s: new Object() }); // ok
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r.s && r.s.toFixed(); // would blow up at runtime
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//// [subtypingWithOptionalProperties.js]
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// subtyping is not transitive due to optional properties but the subtyping algorithm assumes it is for the 99% case
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// returns { s?: number; }
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function f(a) {
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var b = a;
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return b;
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}
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var r = f({ s: new Object() }); // ok
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r.s && r.s.toFixed(); // would blow up at runtime
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