[Python-Dev] iterzip() (original) (raw)

Raymond Hettinger python@rcn.com
Sun, 28 Apr 2002 20:16:30 -0400

From: "Guido van Rossum" <guido@python.org>

Hm, I'm not particularly enamored of the idea of adding 'iter' versions of everything under the sun.

I'm already working on a separate module for iterators galore (and will cross-check to Haskell to make sure I didn't miss anything).

I posted this one separately because zip() eats memory like crazy and because a Python generator version crawls like a snail.

IMHO, This is a better way to loop over multiple sequences and has a chance at becoming the tool of choice. I scanned all of my Python code and found that iterzip() was a better choice in every case except a matrix transpose coded as zip(*mat).

I wish zip() could've been an interator from the start, but now that it isn't, I don't think it's such a big deal. (An iterator version is easily written as a generator.)

In general I'm not keen on increasing the number of builtin functions much.

Ditto. Any chance of moving functions like map(), reduce(), and filter() to a functional module; pow() and divmod() to the math module; or input() to oblivion?

Raymond Hettinger