==== tests/cases/compiler/typesWithDuplicateTypeParameters.ts (6 errors) ====
    class C<T, T> { }
            ~
!!! typesWithDuplicateTypeParameters.ts(1,9): error TS2000: Duplicate identifier 'T'.
    class C2<T, U, T> { }
             ~
!!! typesWithDuplicateTypeParameters.ts(2,10): error TS2000: Duplicate identifier 'T'.
    
    interface I<T, T> { }
                ~
!!! typesWithDuplicateTypeParameters.ts(4,13): error TS2000: Duplicate identifier 'T'.
    interface I2<T, U, T> { }
                 ~
!!! typesWithDuplicateTypeParameters.ts(5,14): error TS2000: Duplicate identifier 'T'.
    
    function f<T, T>() { }
               ~
!!! typesWithDuplicateTypeParameters.ts(7,12): error TS2000: Duplicate identifier 'T'.
    function f2<T, U, T>() { }
                ~
!!! typesWithDuplicateTypeParameters.ts(8,13): error TS2000: Duplicate identifier 'T'.