=== tests/cases/conformance/types/objectTypeLiteral/callSignatures/specializedSignatureWithOptional.ts ===
declare function f(x?: "hi"): void;
>f : Symbol(f, Decl(specializedSignatureWithOptional.ts, 0, 0), Decl(specializedSignatureWithOptional.ts, 0, 35))
>x : Symbol(x, Decl(specializedSignatureWithOptional.ts, 0, 19))

declare function f(x?: string): void;
>f : Symbol(f, Decl(specializedSignatureWithOptional.ts, 0, 0), Decl(specializedSignatureWithOptional.ts, 0, 35))
>x : Symbol(x, Decl(specializedSignatureWithOptional.ts, 1, 19))