Please comment on Draft PEP for Enhanced Generators
jonathan at onegoodidea.com
Wed Jan 30 20:21:37 CET 2002
On 30/1/2002 8:48, in article a38c1u$945$1 at bob.news.rcn.net, "Raymond
Hettinger" <othello at javanet.com> wrote:
> I have written a draft PEP summarizing proposed enhancements to generators:
* New lazy builtins - yup. Except, I'm not convinced of using sys.maxint
in index(). I know that's a big number, but I still get the worrying
feeling that limiting the upper bound is a bad idea. Python 2.2 will
automagically switch to using longs if you hit maxint, but here it will
just terminate without any obvious error message or idea as to why.
* I also prefer using 'indexed' to 'index'. It just seems to read better
to me. Also, I use 'index' as a variable name all the time and wouldn't
want the name clash.
* I'm a big fan of generator comprehensions for symmetry, but I must admit
that I'm not sure they're worth adding new syntax for.
* I'm not convinced about the suggested mechanism for implementing consumers
via re-using the yield keyword with some magic. It just doesn't feel right
to me. It looks too arbitrary [crisps shouldn't melt, they should crunch].
I think you should present an alternative or two. Perhaps introducing new
syntax for consumers, maybe:
x = accept
or some such. Perhaps you should also provide a stronger argument as to
why consumers would be a valuable addition. Picking something from the
standard library and re-writing it is always good. Have you tried the
"nine out of ten cats understood what this code sample did" test?
* Is there a reference implementation for the consumer modification?
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