Typing system vs. Java

Alex Martelli aleaxit at yahoo.com
Mon Aug 6 10:33:57 EDT 2001


"Courageous" <jkraska1 at san.rr.com> wrote in message
news:6dtqmtg3klt5cosohslg742u1o746n1qqb at 4ax.com...
>
> >I haven't seen many such requests.  Anyway, it's clearly trivial
> >to subclass UserList, overriding append and __setitem__ to make
> >sure the items being added satisfy some per-item test (be it
> >a type-test or something more clever) -- is that what you mean?
>
> Pretty much, yep.
>
> BTW, the "requests" for uniform containers I was referring to weren't
> necessarily for Python. :)

In other languages, the "uniform containers" may be FAR more
necessary than they are in Python.  For example, in Java you
currently get the choice -- either a Vector with all of its niceties
BUT strictly Object as contents, OR an array with SOME level of
compile-time homogeneity (unfortunately bogus because of
covariance, but that's another issue) but very low-level operation.
THERE a Generic-Java able (among other things) to supply a
homogeneous "no casts needed on retrieval" equivalent of
Vector has been a sore need for many years.

But the need doesn't generalize to Python:-).


Alex






More information about the Python-list mailing list