On Feb 26, 2006, at 4:20 PM, Ron Adam wrote:
...
> (sigh of relief) Ok, so the following example will still be true.
Yep, no danger of dynamic scoping, be certain of that.
> Maybe something explicit like:
>
>>>> import __main__ as glob
Sure, or the more general ''glob=__import__(__name__)''.
> I'm -1 on adding the intermediate (outer) scopes to functions. I'd
> even
> like to see closures gone completely, but there's probably a reason
> they
> are there. What I like about functions is they are fast, clean up
> behind themselves, and act *exactly* the same on consecutive calls.
Except that the latter assertion is just untrue in Python -- we
already have a bazilion ways to perform side effects, and, since
there is no procedure/function distinction, side effects in functions
are an extremely common thing. If you're truly keen on having the
"exactly the same" property, you may want to look into functional
languages, such as Haskell -- there, all data is immutable, so the
property does hold (any *indispensable* side effects, e.g. I/O, are
packed into 'monads' -- but that's another story).
Closures in Python are often extremely handy, as long as you use them
much as you would in Haskell -- treating data as immutable (and in
particular outer names as unrebindable). You'd think that functional
programming fans wouldn't gripe so much about Python closures being
meant for use like Haskell ones, hm?-) But, of course, they do want
to have their closure and rebind names too...
Alex
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