==== tests/cases/compiler/vararg.ts (8 errors) ====
    module M {
        export class C {
            public f(x:string,...rest:number[]) {
                var sum=0;
                for (var i=0;i<rest.length;i++) {
                    sum+=rest[i];
                }
                result+=(x+": "+sum);
                return result;
            }
    
            public fnope(x:string,...rest:number) {
                                  ~~~~~~~~~~~~~~
!!! A rest parameter must be of an array type.
        
            }
    
            public fonly(...rest:string[]) {
                builder="";
                ~~~~~~~
!!! Cannot find name 'builder'.
                for (var i=0;i<rest.length;i++) {
                    builder+=rest[i];
                    ~~~~~~~
!!! Cannot find name 'builder'.
                }
                return builder;
                       ~~~~~~~
!!! Cannot find name 'builder'.
            }
        }
    }
    
    var x=new M.C();
    var result="";
    result+=x.f(x,3,3); // bad first param
                ~
!!! Argument of type 'C' is not assignable to parameter of type 'string'.
    result+=x.f(3,"hello",3); // bad second param
                ~
!!! Argument of type 'number' is not assignable to parameter of type 'string'.
    result+=x.f("hello",3,3,3,3,3); // ok
    result+=x.f("hello"); // ok varargs length 0
    result+=x.fonly(3); // ok conversion
                    ~
!!! Argument of type 'number' is not assignable to parameter of type 'string'.
    result+=x.fonly(x); // bad param
                    ~
!!! Argument of type 'C' is not assignable to parameter of type 'string'.
    result+=x.fonly("a"); // ok 
    result+=x.fonly("a","b","c","d"); //ok