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=== tests/cases/conformance/expressions/contextualTyping/functionExpressionContextualTyping2.ts ===
// 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
>a0 : Symbol(a0, Decl(functionExpressionContextualTyping2.ts, 8, 3))
>n : Symbol(n, Decl(functionExpressionContextualTyping2.ts, 8, 9))
>s : Symbol(s, Decl(functionExpressionContextualTyping2.ts, 8, 19))
var a1: typeof a0 | ((n: number, s: string) => string);
>a1 : Symbol(a1, Decl(functionExpressionContextualTyping2.ts, 9, 3))
>a0 : Symbol(a0, Decl(functionExpressionContextualTyping2.ts, 8, 3))
>n : Symbol(n, Decl(functionExpressionContextualTyping2.ts, 9, 22))
>s : Symbol(s, Decl(functionExpressionContextualTyping2.ts, 9, 32))
a1 = (foo, bar) => { return true; } // Error
>a1 : Symbol(a1, Decl(functionExpressionContextualTyping2.ts, 9, 3))
>foo : Symbol(foo, Decl(functionExpressionContextualTyping2.ts, 10, 6))
>bar : Symbol(bar, Decl(functionExpressionContextualTyping2.ts, 10, 10))
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