/src/lib/design_patterns/undoable_command.e

 1-- This file is part of a Liberty Eiffel library.
 2-- See the full copyright at the end.
 3--
 4deferred class UNDOABLE_COMMAND
 5   --
 6   -- Another useful Command, that can be undone.
 7   --
 8
 9inherit
10   COMMAND
11
12feature {ANY}
13   undo: COMMAND
14         -- A command that makes the execution of Current undone.
15      deferred
16      end
17
18end -- class UNDOABLE_COMMAND
19--
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