21 lines
1.7 KiB
Plaintext
21 lines
1.7 KiB
Plaintext
tests/cases/conformance/expressions/contextualTyping/functionExpressionContextualTyping2.ts(11,1): error TS2322: Type '(foo: number, bar: string) => boolean' is not assignable to type '((n: number, s: string) => number) | ((n: number, s: string) => string)'.
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Type '(foo: number, bar: string) => boolean' is not assignable to type '(n: number, s: string) => string'.
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Type 'boolean' is not assignable to type 'string'.
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==== tests/cases/conformance/expressions/contextualTyping/functionExpressionContextualTyping2.ts (1 errors) ====
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// A contextual signature S is extracted from a function type T as follows:
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// If T is a function type with exactly one call signature, and if that call signature is non- generic, S is that signature.
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// If T is a union type, let U be the set of element types in T that have call signatures.
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// If each type in U has exactly one call signature and that call signature is non- generic,
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// and if all of the signatures are identical ignoring return types, then S is a signature
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// with the same parameters and a union of the return types.
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// Otherwise, no contextual signature can be extracted from T and S is undefined.
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var a0: (n: number, s: string) => number
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var a1: typeof a0 | ((n: number, s: string) => string);
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a1 = (foo, bar) => { return true; } // Error
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~~
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!!! error TS2322: Type '(foo: number, bar: string) => boolean' is not assignable to type '((n: number, s: string) => number) | ((n: number, s: string) => string)'.
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!!! error TS2322: Type '(foo: number, bar: string) => boolean' is not assignable to type '(n: number, s: string) => string'.
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!!! error TS2322: Type 'boolean' is not assignable to type 'string'. |