ann: Pysch, Scheme runtime environment in Python

[Oleg Paraschenko]

Hello,

I'd like to announce addition to the list of Scheme
interpreters written in the Python language.

Pysch:
http://pysch.sourceforge.net/

I wrote Pysch for my own research goals, but I think
that it may be useful for general public.

Pysch relies on Bigloo to preprocess a source code of
Scheme programs (expand macros) and to save the result
as XML. Pysch interprets only the refined XML.

Pysch supports only a subset of the Scheme functions
library. Anyway, the subset is big enough to run
SXPath and SXSLT code.

Regards, Oleg

 

[David Rush]

Pysch:
http://pysch.sourceforge.net/

Pysch relies on Bigloo to preprocess a source code of
Scheme programs (expand macros) and to save the result
as XML. Pysch interprets only the refined XML.

This should get listed as the most bizarre implementation methodolgy
ever adopted. I think you have definitively showed the equivalence
between s-exprs and XML, if nothing else.

And for the tone-of-voice challenged, I do not intend to convey
sarcasm. Rather I am amazed that such an approach works well
enough to:

Pysch supports only a subset of the Scheme functions
library. Anyway, the subset is big enough to run
SXPath and SXSLT code.

How fast?

david rush

 

[Arich Chanachai]

(e-mail address removed) (Oleg Paraschenko) writes:



This should get listed as the most bizarre implementation methodolgy
ever adopted. I think you have definitively showed the equivalence
between s-exprs and XML, if nothing else.

And for the tone-of-voice challenged, I do not intend to convey
sarcasm. Rather I am amazed that such an approach works well
enough to:




How fast?

david rush

If you had checked the website you would know the answer. It is stated
clearly on the website that it is VERY slow, primarily for research, and
therefore not for production purposes.

 

[Oleg Paraschenko]

Hello David,

And for the tone-of-voice challenged, I do not intend to convey
sarcasm. Rather I am amazed that such an approach works well
enough to:

I'm interested in generative programming and virtual machines.
One of the my suggestions is that it is reasonable to use
a minimal lisp-like core system and scheme-like library as
an universal virtual machine. Indeed, Pysch was a test if this
approach works. Hm, maybe I should write an article now?

How fast?

As slow as possible. Speed was sacrificed in order to produce
a correctly working prototype as soon as possible.

On my Linux computer (PII 450MHz, 512Mb RAM),
calculation of the Ackermann(3,4) gives:

$ time sh -c '(cat ack.xml | (cd ../pysch/pysch/vm; python eval.py))'
Ackermann(3,4) is 125
#unspecified
56.59user 0.26system 1:10.39elapsed 80%CPU (0avgtext+0avgdata 0maxresident)k
0inputs+0outputs (1020major+791minor)pagefaults 0swaps