On Tue, May 31, 2011 at 1:18 PM, Daniel Kluev <dan.kl...@gmail.com> wrote: > On Tue, May 31, 2011 at 2:05 PM, Chris Angelico <ros...@gmail.com> wrote: >> Infinitely-nested scoping is simply one of the casualties of a >> non-declarative language. > > Well, this is not accurate, as you can have 'infinitely-nested > scoping' in python, in form of nested functions. For example, you can > use map(lambda x: <expressions with x, including other > map/filter/reduce/lambda's>, list_of_x), and you will have your > isolated scopes. Although due to lambdas supporting only expressions, > following this style leads to awkward and complicated code (and/or > instead if, map instead for, and so on).
That's an incredibly messy workaround, and would get ridiculous if you tried going many levels in. It's like saying that a C-style 'switch' statement can be implemented in Python using a dictionary of lambdas... and then trying to implement fall-through. But you're right; a lambda does technically create something of a nested scope - albeit one in which the only internal variables are its parameters. Chris Angelico -- http://mail.python.org/mailman/listinfo/python-list