Fix a Doxygen comment error.

The issue was found by CLang.
Fix a Doxygen comment error.

The issue was found by CLang.
Remove a useless semicolon.
Remove a useless semicolon.
Improve a horrible enumerate conversion.

Two improvements were made.
- By adding a default in a case in a switch statement the compiler can
  no longer warn when a member of the enumerate is not handled.
- The exception thrown had no message, so added a message. This also
  required to change the type of the exception to a more appropriate
  type.
Fix a comment typo.
Strip trailing whitespace.