Python vs. Lisp -- please explain

[Kay Schluehr]

Torsten Bronger wrote:
> Hallöchen!
>
> "Paul Boddie" <paul at boddie.org.uk> writes:
>
> > Kay Schluehr wrote:
> >
> >> I would say yes, it is still "proper Python" in that each RPython
> >> program is also a CPython program.
> >
> > I suppose it depends on which direction you're coming from, in
> > that many Python programs just wouldn't be able to run in
> > RPython. But then I can understand the convenience of having a
> > subset of Python that is executable by CPython, but which can also
> > be inspected and processed for other purposes, and whose programs
> > maintain their semantics in both situations.
>
> I'm still afraid of the following scenario: Eventually, people might
> regard "RPython plus type declarations" (or something similar) as
> first-class Python because it's faster and runs on more
> implementations, so they try to stick to it.  So effectively you
> would have changed Python.

I wonder why you believe that it would run on more platforms? This
assertion is justifiable with regard of tiny target hardware - but
else? I do think that "RPython++" could be a viable replacement for C
as a systems programming language BECAUSE it is connected closely to
Python. It is a kind of upside-down evolution: a low level language
emerges from a more high level language. We currently know only the
other side of the story. RPython would just be the common denominator
or the language interface. Gilad Bracha suggested optional type systems
for dynamic languages[1] but as it seems to me RPython would be a fine
candidate for a declarative layer, not Python.

> Maybe I misunderstood something because I could not follow all of
> Kay's text but I think one should not change Python or create a
> look-alike to allow for better implementations.  The language should
> fit my brain rather than an implementation.

It should first of all fit the diversity of a programmers needs. C was
never considered as a hostile brother of Python so why should it be
Pythons own son?

Kay