==== tests/cases/compiler/inOperator.ts (1 errors) ====
    var a=[];
    
    for (var x in a) {}
    
    if (3 in a) {}
    
    var b = '' in 0;
                  ~
!!! The right-hand side of an 'in' expression must be of type 'any', an object type or a type parameter
    
    var c: any;
    var y: number;
    if (y in c) { }