Thought on PEP 204 and 276

[Gustavo Cordova]

> 
> I can't help being disappointed that PEP 204 was rejected. To me,
> 
>   for i in [0:10] :
> 
> is much more intuitive than the PEP 276 version
> 
>   for i in 10 :
> 
> 
> As for the ideas like allowing '[1, 5:10, 20]', combining the syntax
> with list comprehensions, etc I feel the common policy of KISS (ie
> just do the minimal slice-like notation) is a good principle.
> 
> On the issue that it could be confused with slices, consider the
> following...
> 
>   (1, 2)
> 
> Is that a tuple containing the values 1 and 2, or is it the actual
> parameter list for a function call? - you can only tell from the
> context (ie was there a function name, variable containing a lambda or
> whatever to the left). Clearly the slice/range-list dilemma is no more
> confusing than syntax that already exists.
> 
> As for being non-obvious, I'd say it's as obvious as using the slice
> notation for slices.
> 
> In short, PEP 204 seems intuitive to me while PEP 276 makes me worry.
> 
> Am I alone in thinking this?
> 
> -- 
> Steve Horne
> steve at lurking.demon.co.uk
> 

just make an Ints module, with an Ints object (or which inserts
into __builtins__ an Ints object, but that's nasty).

-- clip here --
class _Ints:
  def __init__(self): pass
  def __getitem__(self, range):
    if type(range) != SliceType:
      raise ValueError("The range must be a slice!")
    return xrange(range.start, range.stop, range.step)

Ints = _Ints()
del _Ints
-- clip here --

and Voilà, you can obtain integer ranges with simply:

from Ints import Ints

for x in Ints[10:30:2]:
  do(x)

neato :-)

-gus