51 lines
2.2 KiB
TypeScript
51 lines
2.2 KiB
TypeScript
//// [contextualTypeWithUnionTypeCallSignatures.ts]
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//When used as a contextual type, a union type U has those members that are present in any of
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// its constituent types, with types that are unions of the respective members in the constituent types.
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// Let S be the set of types in U that have call signatures.
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// If S is not empty and the sets of call signatures of the types in S are identical ignoring return types,
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// U has the same set of call signatures, but with return types that are unions of the return types of the respective call signatures from each type in S.
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interface IWithNoCallSignatures {
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foo: string;
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}
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interface IWithCallSignatures {
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(a: number): string;
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}
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interface IWithCallSignatures2 {
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(a: number): number;
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}
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interface IWithCallSignatures3 {
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(b: string): number;
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}
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interface IWithCallSignatures4 {
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(a: number): string;
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(a: string, b: number): number;
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}
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// With no call signature | callSignatures
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var x: IWithNoCallSignatures | IWithCallSignatures = a => a.toString();
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// With call signatures with different return type
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var x2: IWithCallSignatures | IWithCallSignatures2 = a => a.toString(); // Like iWithCallSignatures
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var x2: IWithCallSignatures | IWithCallSignatures2 = a => a; // Like iWithCallSignatures2
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// With call signatures of mismatching parameter type
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var x3: IWithCallSignatures | IWithCallSignatures3 = a => /*here a should be any*/ a.toString();
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// With call signature count mismatch
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var x4: IWithCallSignatures | IWithCallSignatures4 = a => /*here a should be any*/ a.toString();
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//// [contextualTypeWithUnionTypeCallSignatures.js]
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//When used as a contextual type, a union type U has those members that are present in any of
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// its constituent types, with types that are unions of the respective members in the constituent types.
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// With no call signature | callSignatures
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var x = function (a) { return a.toString(); };
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// With call signatures with different return type
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var x2 = function (a) { return a.toString(); }; // Like iWithCallSignatures
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var x2 = function (a) { return a; }; // Like iWithCallSignatures2
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// With call signatures of mismatching parameter type
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var x3 = function (a) { return a.toString(); };
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// With call signature count mismatch
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var x4 = function (a) { return a.toString(); };
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