tests/cases/compiler/recursiveFunctionTypes.ts(1,35): error TS2322: Type 'number' is not assignable to type '() => typeof fn'. tests/cases/compiler/recursiveFunctionTypes.ts(3,5): error TS2322: Type '() => typeof fn' is not assignable to type 'number'. tests/cases/compiler/recursiveFunctionTypes.ts(4,5): error TS2322: Type '() => typeof fn' is not assignable to type '() => number'. Type '() => typeof fn' is not assignable to type 'number'. tests/cases/compiler/recursiveFunctionTypes.ts(11,16): error TS2355: A function whose declared type is neither 'void' nor 'any' must return a value or consist of a single 'throw' statement. tests/cases/compiler/recursiveFunctionTypes.ts(12,16): error TS2355: A function whose declared type is neither 'void' nor 'any' must return a value or consist of a single 'throw' statement. tests/cases/compiler/recursiveFunctionTypes.ts(17,5): error TS2322: Type '() => I' is not assignable to type 'number'. tests/cases/compiler/recursiveFunctionTypes.ts(22,5): error TS2345: Argument of type 'number' is not assignable to parameter of type '(t: typeof g) => void'. tests/cases/compiler/recursiveFunctionTypes.ts(25,1): error TS2322: Type 'number' is not assignable to type '() => any'. tests/cases/compiler/recursiveFunctionTypes.ts(30,1): error TS2394: Overload signature is not compatible with function implementation. tests/cases/compiler/recursiveFunctionTypes.ts(33,1): error TS2346: Supplied parameters do not match any signature of call target. tests/cases/compiler/recursiveFunctionTypes.ts(34,4): error TS2345: Argument of type 'string' is not assignable to parameter of type '{ (): typeof f6; (a: typeof f6): () => number; }'. tests/cases/compiler/recursiveFunctionTypes.ts(42,1): error TS2346: Supplied parameters do not match any signature of call target. tests/cases/compiler/recursiveFunctionTypes.ts(43,4): error TS2345: Argument of type 'string' is not assignable to parameter of type '{ (): typeof f7; (a: typeof f7): () => number; (a: number): number; (a?: typeof f7): typeof f7; }'. ==== tests/cases/compiler/recursiveFunctionTypes.ts (13 errors) ==== function fn(): typeof fn { return 1; } ~ !!! error TS2322: Type 'number' is not assignable to type '() => typeof fn'. var x: number = fn; // error ~ !!! error TS2322: Type '() => typeof fn' is not assignable to type 'number'. var y: () => number = fn; // ok ~ !!! error TS2322: Type '() => typeof fn' is not assignable to type '() => number'. !!! error TS2322: Type '() => typeof fn' is not assignable to type 'number'. var f: () => typeof g; var g: () => typeof f; function f1(d: typeof f1) { } function f2(): typeof g2 { } ~~~~~~~~~ !!! error TS2355: A function whose declared type is neither 'void' nor 'any' must return a value or consist of a single 'throw' statement. function g2(): typeof f2 { } ~~~~~~~~~ !!! error TS2355: A function whose declared type is neither 'void' nor 'any' must return a value or consist of a single 'throw' statement. interface I { } function f3(): I { return f3; } var a: number = f3; // error ~ !!! error TS2322: Type '() => I' is not assignable to type 'number'. class C { static g(t: typeof C.g){ } } C.g(3); // error ~ !!! error TS2345: Argument of type 'number' is not assignable to parameter of type '(t: typeof g) => void'. var f4: () => typeof f4; f4 = 3; // error ~~ !!! error TS2322: Type 'number' is not assignable to type '() => any'. function f5() { return f5; } function f6(): typeof f6; function f6(a: typeof f6): () => number; ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ !!! error TS2394: Overload signature is not compatible with function implementation. function f6(a?: any) { return f6; } f6("", 3); // error (arity mismatch) ~~~~~~~~~ !!! error TS2346: Supplied parameters do not match any signature of call target. f6(""); // ok (function takes an any param) ~~ !!! error TS2345: Argument of type 'string' is not assignable to parameter of type '{ (): typeof f6; (a: typeof f6): () => number; }'. f6(); // ok declare function f7(): typeof f7; declare function f7(a: typeof f7): () => number; declare function f7(a: number): number; declare function f7(a?: typeof f7): typeof f7; f7("", 3); // error (arity mismatch) ~~~~~~~~~ !!! error TS2346: Supplied parameters do not match any signature of call target. f7(""); // ok (function takes an any param) ~~ !!! error TS2345: Argument of type 'string' is not assignable to parameter of type '{ (): typeof f7; (a: typeof f7): () => number; (a: number): number; (a?: typeof f7): typeof f7; }'. f7(); // ok