# [Python-Dev] PEP 201 - Parallel iteration

**Peter Schneider-Kamp
**
peter@schneider-kamp.de

*Tue, 18 Jul 2000 11:23:38 +0000*

Ken Manheimer wrote:
>*
*>* Evan Simpson (a colleague here at digicool, who'd be a good addition
*>* to python-dev) noticed that unzip is unnecessary - zip is its own
*>* inverse. Since this is a worthwhile observation, i'll indulge a bit
*>* and present it in evan's terms - particularly noting a different
*>* packaging that i think is pretty cool, as methods on sequences.
*
Yeah, but this is only true if we let zip() be a sequence
method (or a function taking a sequence):
for x,y in [[1, 2, 3], [4, 5, 6]].zip():
for x,y in zip([[1, 2, 3], [4, 5, 6]]):
for x,y in zip([1, 2, 3], [4, 5, 6]):
To be fair I'll do second one:
a = [1, 2, 3]
b = [4, 5, 6]
c = [7, 8, 9]
for x,y,z in [a, b, c].zip():
for x,y,z in zip([a, b, c]):
for x,y,z in zip(a, b, c):
I still think the third form is more explicit, but I am
+0 on making zip() a sequence method.
Peter
--
Peter Schneider-Kamp ++47-7388-7331
Herman Krags veg 51-11 mailto:peter@schneider-kamp.de
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