==== tests/cases/compiler/instanceofOperator.ts (6 errors) ====
    // Spec:
    // The instanceof operator requires the left operand to be of type Any or an object type, and the right 
    // operand to be of type Any or a subtype of the ‘Function’ interface type. The result is always of the 
    // Boolean primitive type.
    
    class Object { }
          ~~~~~~
!!! Duplicate identifier 'Object'.
    var obj: Object;
    
    
    
    4 instanceof null; 
    ~
!!! The left-hand side of an 'instanceof' expression must be of type 'any', an object type or a type parameter.
    
    // Error and should be error
    obj instanceof 4;
                   ~
!!! The right-hand side of an 'instanceof' expression must be of type 'any' or of a type assignable to the 'Function' interface type.
    Object instanceof obj;
                      ~~~
!!! The right-hand side of an 'instanceof' expression must be of type 'any' or of a type assignable to the 'Function' interface type.
    
    // Error on left hand side
    null instanceof null;
    ~~~~
!!! The left-hand side of an 'instanceof' expression must be of type 'any', an object type or a type parameter.
    obj instanceof Object;
    undefined instanceof undefined;
    ~~~~~~~~~
!!! The left-hand side of an 'instanceof' expression must be of type 'any', an object type or a type parameter.