Loop-and-a-half (Re: Curious assignment behaviour)

[Michael Hudson]

Donn Cave wrote:


> I am not a big fan of the for i in range() idiom, myself.  But you
> aren't required to use it.  If you want the effect of 
> 
>    for (i = 0; i<n; i++) {
>        --- do stuff --
>    }
> 
> then in Python, you write
> 
>    i = 0
>    while i < n:
>        --- do stuff --
>        i = i + 1
> 
> "wc" says that's 7 more characters to type, which would be a concern
> if you have to engrave it on linoleum or something.  And you have to
> avoid "continue". 


i = 0
while i < n:
     try:
         --- do stuff ---
     finally:
         i += 1

('prolly only works in relatively recent Pythons)

Anyone using this as an idiom deserves a slap, though.

> It seems to me this is the loop construct that people
> must use, though, if they're going to expect the tricks they learn
> in C to work. 


Such people already have major problems, no?

> Python's "for" loop is really a different thing, not
> something I ever found all that cutesy-poo, just a sequence thing
> that you see in plenty of languages but not C.


It is subtly changing in 2.2, of course.


Cheers,
M.