Why GIL? (was Re: what's the point of rpython?)

[Aahz]

In article <7xr62ufv1c.fsf at ruckus.brouhaha.com>,
Paul Rubin  <http://phr.cx@NOSPAM.invalid> wrote:
>aahz at pythoncraft.com (Aahz) writes:
>>
>> CPython's "primitive" storage management has a lot to do with the
>> simplicity of interfacing CPython with external libraries.  Any solution
>> that proposes to get rid of the GIL needs to address that.
>
>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?
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

Weinberg's Second Law: If builders built buildings the way programmers wrote 
programs, then the first woodpecker that came along would destroy civilization.