[Sorry for over-quoting, I am not sure how to trim this properly] Steven D'Aprano wrote:
> On Thu, 23 Jun 2011 09:30 am Thomas 'PointedEars' Lahn wrote: >> Mel wrote: >>> Steven D'Aprano wrote: >>>> I *guess* that what you mean by "writable iterators" is that rebinding >>>> e should change seq in place, i.e. you would expect that seq should now >>>> equal [42, 42]. Is that what you mean? It's not clear. >>>> >>>> Fortunately, that's not how it works, and far from being a >>>> "limitation", it would be *disastrous* if iterables worked that way. I >>>> can't imagine how many bugs would occur from people reassigning to the >>>> loop variable, forgetting that it had a side-effect of also reassigning >>>> to the iterable. Fortunately, Python is not that badly designed. >>> >>> And for an iterator like >>> >>> def things(): >>> yield 1 >>> yield 11 >>> yield 4 >>> yield 9 >>> >>> I don't know what it could even mean. >> >> <http://docs.python.org/reference/simple_stmts.html#the-yield-statement> >> >> You could have tried to debug. > > I think you have missed the point of Mel's comment. He knows what the > yield statement does. He doesn't know what it would mean to "write to" an > iterator like things(). > > Neither do I. AIUI the OP is referring to write accesses to the iteration variable (for want of a better term), not being aware what iterators are. -- PointedEars Bitte keine Kopien per E-Mail. / Please do not Cc: me. -- http://mail.python.org/mailman/listinfo/python-list
