         var testSubject = self
         if count(testSubject) > 0 {
             if testSubject[0] == "-" {
-                testSubject = testSubject.substringFromIndex(advance(testSubject.startIndex, 1))
+                testSubject = testSubject.decapitate()
             }
         }
         
         if count(testSubject) > 0 {
             if testSubject[0] == "$" {
-                testSubject = testSubject.substringFromIndex(advance(testSubject.startIndex, 1))
+                testSubject = testSubject.decapitate()
             } else {
                 return false
             }

    public func isValidInteger () -> Bool {
        if count(self) > 0 {
            if self[0] == "-" {
                return substringFromIndex(advance(startIndex, 1)).isValidWholeNumber()
            }
            return isValidWholeNumber()
        } else {

    }
    
    
    
    
    
    
    
    // MARK: Substring
    public func decapitate () -> String {
        if count(self) > 0 {
            return substringFromIndex(advance(startIndex, 1))
        }
        return ""
    }
    
    
}