-data RnMode = SourceMode -- Renaming source code
- | InterfaceMode -- Renaming interface declarations.
+data RnMode = SourceMode -- Renaming source code
+ | InterfaceMode -- Renaming interface declarations.
+ | CmdLineMode -- Renaming a command-line expression
+
+isInterfaceMode InterfaceMode = True
+isInterfaceMode _ = False