       return false
     else
       for char in @value
-        if not char in alnums
+        if not (char in alnums)
           return false
       return true
 

      return false
    else
      for char in @value
        if not char in lowers
          return false
      return true
  

      return false
    else
      for char in @value
        if not (char in uppers)
          return false
      return true

