switch

[Matt McCredie]

hong zhang <henryzhang62 <at> yahoo.com> writes:

> 
> List,
> 
> Python does not have switch statement. Any other option does similar work?
> Thanks for help.
> 
> --henry
> 
>       

I see a couple of people have mentioned using a dictionary. If the value that 
you are switching on is a string, or could be made into one, you can use a 
variant of the command dispatch pattern.


class MyCommandDispatcher(object):
    def do_a(self):
      # do stuff
    
    def do_b(self):
      # do stuff

    def do_5(self):
      # do stuff

    def default(self):
      # do stuff

    def switch(self, option):
        getattr(self, 'do_' + str(option), self.default)()


d = MyCommandDispatcher()
d.switch('a')
d.switch(5)


This isn't _much_ more coding than using the dictionary method, and is pretty 
readable. This is also a common pattern in python.


Matt