On Fri, 19 Jun 2015 07:29 pm, Robin Becker wrote: > I'm trying to overcome a recursive import issue in reportlab. > > Module reportlab.rl_config uses various sources (eg ~/.reportlab_settings) > to initialize various defaults eg canvas_basefontname. If a user wants to > utilize reportlab to set up such a default, it's not possible to do so in > the settings file because a recursive import would occur. Normal defaults > are always primitive python objects eg float/int/str etc etc.
I'm afraid I don't understand what you are trying to say here. Why can't the user just set up "such a default" e.g. canvas_basefontname. Surely that is a string, e.g. "Comic Sans". Why will a recursive import occur? If the user doesn't want a recursive import, they need only ensure that they don't import anything that relies on rl_config. > If I make the rl_config module into an object I'd just like to point out that modules are already objects. py> import sys py> isinstance(sys, object) True > (using the GvR blessed approach indicated here > http://stackoverflow.com/questions/2447353/getattr-on-a-module) then I can > use callables in the settings module and get them evaluated lazily which > overcomes the recursion. > > Are there any gotcha's that need to be considered when using this instance > as module approach? My trial implementation seems to work, but it's not > clear exactly how a module differs from an instance. Um, precisely the same way an int or a str or an instance of Foo class differs from an instance. An instance of what? > I have set various > dunders on the instance eg __file__, __doc__, __all__ & __name__ and I > made the object a borg, but it still seems a bit hacky. Making it a borg is one concrete difference. Modules are singletons, not borgs, so anyone who does if the_thing is somemodule may be surprised. I wouldn't necessarily worry about borgifying the module proxy, since the import mechanics will ensure[1] it remains a singleton. But frankly, this approach sounds complex and complicated, and we know what the Zen says about them. [1] For some definition of "ensure". -- Steven -- https://mail.python.org/mailman/listinfo/python-list
