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

    public func isValidInteger () -> Bool {
        if count(self) > 0 {
            if self[0] == "-" {
                return decapitate().isValidWholeNumber()
            }
            return isValidWholeNumber()
        } else {
