import os class MoveFileCommand(object): def __init__(self, src, dest): self.src = src self.dest = dest def execute(self): self() def __call__(self): print('renaming {} to {}'.format(self.src, self.dest)) os.rename(self.src, self.dest) def undo(self): print('renaming {} to {}'.format(self.dest, self.src)) os.rename(self.dest, self.src) if __name__ == "__main__": command_stack = [] # commands are just pushed into the command stack command_stack.append(MoveFileCommand('foo.txt', 'bar.txt')) command_stack.append(MoveFileCommand('bar.txt', 'baz.txt')) # they can be executed later on for cmd in command_stack: cmd.execute() # and can also be undone at will for cmd in reversed(command_stack): cmd.undo()
点击run it 运行之!!!