removing list comprehensions in Python 3.0

[Kay Schluehr]

Leif K-Brooks schrieb:
> Kay Schluehr wrote:
> >>>>list.from_str("abc")
> >
> > list("a", "b", "c" )
>
>
> I assume we'll also have list.from_list, list.from_tuple,
> list.from_genexp, list.from_xrange, etc.?

One might unify all those factory functions into a single
list.from_iter that dispatches to the right constructor that still
lives under the hood. More conceptually: there is some abstract iter
base class providing a from_iter method which may be overwritten in
concrete subclasses like tuple, str or list.

I would further suggest a lazy iterator used to evaluate objects when
they get accessed the first time:

>>> l = lazy( math.exp(100) , 27 )
<lazy-iterator object at 0x4945f0>
>>> l[1]
27

The first element won't ever be evaluated if it does not get accessed
explicitely. This is some very special kind of partial
evaluation/specialization.

Kay