tests/cases/compiler/overloadingOnConstants2.ts(8,1): error TS2382: Specialized overload signature is not assignable to any non-specialized signature. tests/cases/compiler/overloadingOnConstants2.ts(9,1): error TS2382: Specialized overload signature is not assignable to any non-specialized signature. tests/cases/compiler/overloadingOnConstants2.ts(15,13): error TS2345: Argument of type 'string' is not assignable to parameter of type '"bye"'. tests/cases/compiler/overloadingOnConstants2.ts(19,1): error TS2382: Specialized overload signature is not assignable to any non-specialized signature. ==== tests/cases/compiler/overloadingOnConstants2.ts (4 errors) ==== class C { private x = 1; } class D extends C {} class E { private y = 1; } function foo(x: "hi", items: string[]): D; ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ !!! error TS2382: Specialized overload signature is not assignable to any non-specialized signature. function foo(x: "bye", items: string[]): E; ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ !!! error TS2382: Specialized overload signature is not assignable to any non-specialized signature. function foo(x: string, items: string[]): C { return null; } var a: D = foo("hi", []); // D var b: E = foo("bye", []); // E var c = foo("um", []); // error ~~~~ !!! error TS2345: Argument of type 'string' is not assignable to parameter of type '"bye"'. //function bar(x: "hi", items: string[]): D; function bar(x: "bye", items: string[]): E; ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ !!! error TS2382: Specialized overload signature is not assignable to any non-specialized signature. function bar(x: string, items: string[]): C; function bar(x: string, items: string[]): C { return null; } var d: D = bar("hi", []); // D var e: E = bar("bye", []); // E var f: C = bar("um", []); // C