==== tests/cases/compiler/classCannotExtendVar.ts (1 errors) ====
    var Markup;
    
    class Markup {
          ~~~~~~
!!! classCannotExtendVar.ts(3,7): error TS2000: Duplicate identifier 'Markup'. Additional locations:
!!! 	classCannotExtendVar.ts(1,5)
        constructor() {
        }
    }
    