twoMergedInterfacesWithDifferingOverloads.ts(23,9): error TS2454: Variable 'b' is used before being assigned.
twoMergedInterfacesWithDifferingOverloads.ts(36,10): error TS2454: Variable 'c' is used before being assigned.
twoMergedInterfacesWithDifferingOverloads.ts(50,10): error TS2454: Variable 'd' is used before being assigned.


==== twoMergedInterfacesWithDifferingOverloads.ts (3 errors) ====
    // interfaces that merge must not have members that conflict
    
    interface A {
        foo(x: number): number;
        foo(x: string): string;
    }
    
    interface A {
        foo(x: Date): Date;
    }
    
    interface B<T> {
        foo(x: T): number;
        foo(x: string): string;
    }
    
    interface B<T> {
        foo(x: T): Date;
        foo(x: Date): string;
    }
    
    var b: B<boolean>;
    var r = b.foo(true); // returns Date
            ~
!!! error TS2454: Variable 'b' is used before being assigned.
    
    // add generic overload
    interface C<T, U> {
        foo(x: T, y: U): string;
        foo(x: string, y: string): number;
    }
    
    interface C<T, U> {
        foo<W>(x: W, y: W): W;
    }
    
    var c: C<boolean, Date>;
    var r2 = c.foo(1, 2); // number
             ~
!!! error TS2454: Variable 'c' is used before being assigned.
    
    // add generic overload that would be ambiguous
    interface D<T, U> {
        a: T;
        b: U;
        foo<A>(x: A, y: A): U;
    }
    
    interface D<T, U> {
        foo<W>(x: W, y: W): T;
    }
    
    var d: D<boolean, Date>;
    var r3 = d.foo(1, 1); // boolean, last definition wins
             ~
!!! error TS2454: Variable 'd' is used before being assigned.