closures and dynamic binding

Michele Simionato michele.simionato at
Fri Oct 3 11:24:42 CEST 2008

On Oct 3, 10:44 am, greg <g... at> wrote:
> So if anything were to be done to the language to
> fix this, it really should be focused on fixing the
> semantics of the for-loop. Unfortunately, the
> fact that the loop variable leaks out of the scope
> of the loop is regarded as a feature, so anything
> which changes that seems to be a non-starter.

And Guido stated many times in the past that he is happy with the for
loop as it is,
so I don't think this will never change, even if the question keep
getting asked here
and there.
Notice that even generator expressions, where the loop variable does
not leak outside the loop,
have the same behavior.
The behavior of the list comprehension is a good test of how much
functional a language is;
Common Lisp and Python behaves in the same way (there is a single loop
variable which is
mutated at each iteration) wherea Scheme and Haskell introduce a new
binding at each iteration.

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