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