[MERGE] Support for lazy registation of commands

[Lukáš Lalinský]

Dňa Ne, 2008-08-24 o 12:03 +0300, Alexander Belchenko napísal:
> Lukáš Lalinský пишет:
> > Dňa Ne, 2008-08-24 o 11:50 +0300, Alexander Belchenko napísal:
> >> +class LazyCommandProxy(object):
> >> +
> >> +    def __init__(self, module, name, aliases):
> >> +        self._module = module
> >> +        self._name = name
> >> +        self.aliases = aliases
> >> +        self.__name__ = name
> >> +
> >> +    def __call__(self, *args, **kwargs):
> >> +        cmd_module = __import__(self._module, globals(), locals(), [True])
> >> +        cmd_class = getattr(cmd_module, self._name)
> >> +        return cmd_class(*args, **kwargs)
> >>
> >>
> >> Why for you pass [True] as last argument to __import__? IMO, you don't need
> >> to pass there anything. According to Python documentation 4th argument
> >> lists the names that should be imported from module. So importing name
> >> 'True' is useless IIUC.
> > 
> > Because self._module might be in form 'bzrlib.plugins.foo' and I want the 'foo'
> > module, not 'bzrlib':
> > 
> >   When the name variable is of the form package.module, normally, the
> >   top-level package (the name up till the first dot) is returned, not the
> >   module named by name. However, when a non-empty fromlist argument is
> >   given, the module named by name is returned.
> 
> Why in this case you do not use [self._name]?

Because it's not necessary, the fromlist is not used for anything but
checking that it's not empty.

Lukas