[Python-Dev] accumulator display syntax

[Skip Montanaro]

    Tim> [Skip Montanaro]
    >> How much more expensive

    Tim> Stop right there.

Okay, but I couldn't resist. ;-)

    >> for f in math.sin, math.cos, math.tan:
    >>    squares = (f(x)**2 for x in inputs)
    >>    plot(squares)

    Tim> Despite the similar appearance, that does something very different,
    ...
    >> which would work without reiterability, right?

    Tim> Yup.

I shouldn't have mentioned performance.  The above was really the point I
was getting at.  The mention of performance was simply because I couldn't
understand why reiterability would be necessary in your example.  I see you
were just pointing out that someone not understanding the underlying nature
of the generator would assume your example would work *and* save cycles
because the definition of the generator expression was hoisted out of the
loop.

Skip