Python complaints

[David Ascher]

On Wed, 24 Nov 1999, Eric Jacobs wrote:

> I don't know if I like that syntax. Taking a slice
> of what? If I had to replace range, I'd go with:
> 
>    for i in Int[1:20:3]:
>       ...
> 
> Here Int is an object that represents a list of all
> integers. We take a slice of it... and get exactly
> what we expect.

> Either way, the semantics of lists with an infinite
> number of elements or negative indices would have
> to be cleared up somewhat. That would be a good
> thing.

Without dealing with the last paragraph, you can fake it now, with
something like (barely tested):

import types
class XRangeClass:
    def __getitem__(self, item):
	if type(item) == types.SliceType:
	    if item.start is None:
		start = 0
	    else:
		start = item.start
	    if item.step is None: 
		step = 1
	    else:
		step = item.step
	    if item.stop is None:
		stop = sys.maxint 
	    else:
		stop = item.stop
	    return xrange(start, stop, step)
	elif type(item) == types.IntType:
	    return item
	else:
	    raise ValueError, "XRanges needs to be sliced with indices or slices"
    def __getslice__(self, start, stop):
	return self.__getitem__(slice(start, stop, None))

Int = XRangeClass()