[Python-Dev] listcomps vs. for loops
Delaney, Timothy C (Timothy)
tdelaney at avaya.com
Tue Oct 21 19:39:03 EDT 2003
> From: Guido van Rossum [mailto:guido at python.org]
> > > for x in R:
> > > ...
> > > print x
> > For which reason I propose that Python 3.0 have the control name in
> > any for expression be "local" to the expression ;)
> What expression?
Sorry - I meant statement.
> If you're talking about making
> x = None
> for x in R: pass
> print x # last item of R
> illegal, forget it. That's too darn useful.
Note the winking smiley above :) Although I do find the scope limiting in:
for (int i=0; i < 10; ++i)
to be a nice feature of C++ (good god - did I just say that?) and hate that the implementation in MSVC is broken and the control variable leaks.
> No, and no; we already went over this (but I don't blame you for not
> reading every msg in this thread :-). It does mean that we have to
> start issuing proper deprecation warnings, and maybe we won't be able
> to properly fix the LC scope thing before 3.0.
Yeah - I realised later that the discussion was hidden in the accumulator syntax thread.
I definitely wouldn't find it confusing, but I've been a proponent of not leaking the control variable all along :)
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