==== tests/cases/compiler/typeParameterHasSelfAsConstraint.ts (2 errors) ====
    function foo<T extends T>(x: T): number {
                 ~~~~~~~~~~~
!!! typeParameterHasSelfAsConstraint.ts(1,14): error TS2229: Constraint of a type parameter cannot reference any type parameter from the same type parameter list.
        return x;
               ~
!!! typeParameterHasSelfAsConstraint.ts(2,12): error TS2011: Cannot convert 'T' to 'number'.
    }
     
    