==== tests/cases/compiler/indexSignatureTypeCheck.ts (4 errors) ====
    interface IPropertySet {
    
        [index: string]: any;
    
    }
    
    
    var ps: IPropertySet = null;
    var index: any = "hello";
    ps[index] = 12;
    
    
    interface indexErrors {
        [p2?: string];
         ~~
!!! An index signature parameter cannot have a question mark.
        [...p3: any[]];
            ~~
!!! An index signature cannot have a rest parameter.
        [p4: string, p5?: string];
         ~~
!!! An index signature must have exactly one parameter.
        [p6: string, ...p7: any[]];
         ~~
!!! An index signature must have exactly one parameter.
    }