[Python-Dev] A `cogen' module - an observation

Greg Ewing greg@cosc.canterbury.ac.nz
Tue, 27 Aug 2002 18:14:51 +1200 (NZST)

> [f(x, y) for x in X for y in Y] 
>   is equivalent to:
> [f(x, y) for x, y in cartesian(X, Y)] 

Hmmm, in other words, cartesian() is a lazy version
of zip().

(Given its intended use, I always thought zip()
should have been lazy from the beginning, but
the BDFL thought otherwise.)

Greg Ewing, Computer Science Dept, +--------------------------------------+
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