what's the point of rpython?

[Paul Rubin]

IMO it's possible to rewrite only the core while keeping the refcount
API for external compatibility, but a tracing GC API in portable C is
hideous.

It's done all the time for other languages, and is less hassle than
the incref/decref stuff and having to remember the difference between
owned and borrowed references, etc.

Enough to make me want to find or make a better implementation language.

There is a lot to be said for this, including the self-respect that
comes from a language being able to host its own implementation.

 

[Mike]

The python devs seem to
consider the GIL a non-issue, though they may change their mind in 3
years when we all have 32 core desktops,

For what it's worth, I am currently using Python to perform a
scientific computation on 1400+ cores, and it seems to work fairly
well. (http://greylag.org/ if you're curious.)

There are a number of things that annoy me about Python (even though
it's my favorite everyday language), but the GIL isn't among them.

The rare cases where the GIL is truly a problem can be balanced
against the large majority where threading is simply inappropriate
anyway. That the latter might help compulsive threaders kick their
habit (or at least head for more convoluted horizons) might be
considered a virtue.

Mike

 

[Aahz]

This, I don't understand. Other languages like Lisp and Java and
Haskell have foreign function interfaces that easier to program than
Python's, -and- they don't use reference counts. There's usually some
primitive to protect objects from garbage collection while the foreign
function is using them, etc. The Java Native Interface (JNI) and the
Haskell FFI are pretty well documented. The Emacs Lisp system is not
too hard to figure out from examining the source code, etc.

This is the first time I've heard about Java being easier to interface
than Python. I don't work at that level myself, so I rely on the
informed opinions of other people; can you provide a summary of what
makes those FFIs easier than Python?