python-patterns/command.py at master · masterp4dev/python-patterns · GitHub

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#!/usr/bin/env python
# -*- coding: utf-8 -*-

importos


classMoveFileCommand(object):

def__init__(self, src, dest):
self.src=src
self.dest=dest

defexecute(self):
print('renaming {} to {}'.format(self.src, self.dest))
os.rename(self.src, self.dest)

defundo(self):
print('renaming {} to {}'.format(self.dest, self.src))
os.rename(self.dest, self.src)


defmain():
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
forcmdincommand_stack:
cmd.execute()

# and can also be undone at will
forcmdinreversed(command_stack):
cmd.undo()

if__name__=="__main__":
main()

### OUTPUT ###
# renaming foo.txt to bar.txt
# renaming bar.txt to baz.txt
# renaming baz.txt to bar.txt
# renaming bar.txt to foo.txt