==== tests/cases/conformance/types/objectTypeLiteral/callSignatures/typeParameterUsedAsTypeParameterConstraint.ts (18 errors) ====
    // Type parameters are in scope in their own and other type parameter lists
    
    function foo<T, U extends T>(x: T, y: U): T {
                    ~~~~~~~~~~~
!!! Constraint of a type parameter cannot reference any type parameter from the same type parameter list.
        x = y;
        ~
!!! Type 'U' is not assignable to type 'T'.
        return y;
               ~
!!! Type 'U' is not assignable to type 'T'.
    }
    
    function foo2<U extends T, T>(x: T, y: U): T {
                  ~~~~~~~~~~~
!!! Constraint of a type parameter cannot reference any type parameter from the same type parameter list.
        x = y;
        ~
!!! Type 'U' is not assignable to type 'T'.
        return y;
               ~
!!! Type 'U' is not assignable to type 'T'.
    }
    
    var f = function <T, U extends T>(x: T, y: U): T {
                         ~~~~~~~~~~~
!!! Constraint of a type parameter cannot reference any type parameter from the same type parameter list.
        x = y;
        ~
!!! Type 'U' is not assignable to type 'T'.
        return y;
               ~
!!! Type 'U' is not assignable to type 'T'.
    }
    
    var f2 = function <U extends T, T>(x: T, y: U): T {
                       ~~~~~~~~~~~
!!! Constraint of a type parameter cannot reference any type parameter from the same type parameter list.
        x = y;
        ~
!!! Type 'U' is not assignable to type 'T'.
        return y;
               ~
!!! Type 'U' is not assignable to type 'T'.
    }
    
    var f3 = <T, U extends T>(x: T, y: U): T => {
                 ~~~~~~~~~~~
!!! Constraint of a type parameter cannot reference any type parameter from the same type parameter list.
        x = y;
        ~
!!! Type 'U' is not assignable to type 'T'.
        return y;
               ~
!!! Type 'U' is not assignable to type 'T'.
    }
    
    var f4 = <U extends T, T>(x: T, y: U): T => {
              ~~~~~~~~~~~
!!! Constraint of a type parameter cannot reference any type parameter from the same type parameter list.
        x = y;
        ~
!!! Type 'U' is not assignable to type 'T'.
        return y;
               ~
!!! Type 'U' is not assignable to type 'T'.
    }