PEP 284, Integer for-loops (code bash?)
Laura Creighton
lac at strakt.com
Sat Mar 9 13:09:25 EST 2002
> Laura Creighton writes:
> > I think that it
> > would have been nice if when Guido was designing the language he
> > used Haskall's syntax for loops. But he didn't.
>
> I *still* haven't found time to learn Haskall, and a quick browse of the
> docs didn't get me anywhere. Can you summarize what Haskall's syntax
> for loops IS? I realize this is a little off topic, but I'm curious.
>
> -- Michael Chermside
>
1. Michael! Your Computer thinks its April! You are making
python archives one month ahead of yourself!
(see: http://mail.python.org/pipermail/python-list/2002-April/091714.html)
2. Haskell, which I mispelt, shame on me, I know better, is a
functional language. It has functional syntax - don't go there looking
for a 'for loop'. However, it also has list comprehensions, (which is
where we got them from, I think). So, what I meant was 'I wish that
Guido had used Haskell's syntax for arithmetic sequences in Python's
for loops'. That is as follows:
[1..10] => [1,2,3,4,5,6,7,8,9,10]
[1,3..8] => [1,3,5,7]
[1,3..] => [1,3,5,7,9, ... (infinite sequence)
This is not restricted to numbers, char works great.
['A','B'..'Z'] => the upper case letters in English in alphabetical order
you can also roll your own:
If you make a user-defined enumerated class, such as statWisdom,
you can use it like this:
[inane..enlightened] => [inane, stupid, idiotic, uneducated,
educated, learned, wise, enlightened]
I have probably forgotten something, somebody else can add it.
3. Make the time to learn Haskell. It is simply too much fun.
Laura Creighton
More information about the Python-list
mailing list