On 6/30/06, Andrew Koenig <[EMAIL PROTECTED]> wrote: > > I read "a la Scheme" here as "actually nothing like Scheme, except I > > want a non-tricky way to rebind a name from an enclosing scope within > > an enclosed scope". > > Almost. What I really want is for it to be possible to determine the > binding of every name by inspecting the source text of the program. Right > now, it is often possible to do so, but sometimes it isn't.
Then your example def f(): return x x = 42 print f() is entirely well-defined -- x is a global and the compiler in fact generates code that benefits from knowing that it's not a local. Python knows which locals there are; also which locals there are in surrounding function scopes. It *could* also know which globals and builtins there are, except the language currently allows dynamic rebinding of module-level variables so that they replace builtins. E.g. def f(): return len([]) print f() # prints 0 def len(x): return "booh" print f() # prints "booh" del len print f() # prints 0 again Worse, instead if explicitly overriding len in the module, it could have been an assignment to __main__.len in some other module. We've been thinking on how to deal with this for years, since nobody really likes it in all its freedom. -- --Guido van Rossum (home page: http://www.python.org/~guido/) _______________________________________________ Python-Dev mailing list Python-Dev@python.org http://mail.python.org/mailman/listinfo/python-dev Unsubscribe: http://mail.python.org/mailman/options/python-dev/archive%40mail-archive.com
