Please enlighten me about PyPy

[Steve Holden]

Kevin Yuan wrote:
> 
> 
> 21 Dec 2005 19:33:20 -0800, Luis M. González <luismgz at gmail.com 
> <mailto:luismgz at gmail.com>>:
> 
>     ... ...
>     This implementation requires a minimal core, writen in a restricted
>     subset of python called "rpython". This subset avoids many of the most
>     dynamic aspects of python, making it easier to authomatically translate
>     it to C through a tool that uses top-notch type inference techniques.
> 
> 
> Why not directly write the minimal core in C?
> 
> 
Because then you'd have to maintain it in C. This way, once you have the 
first working translator you can translate it into C to improve its 
performance, and use it to translate the *next* working translator, and 
so on. Consequently your maintenance work is done on the Python code 
rather than hand-translated C.

Fairly standard bootstrapping technique, though it's sometimes difficult 
to appreciate the problems involved in writing a compiler for language X 
in X itself. Typical is the fact that the compiler for version m has to 
be written in version (m-1), for example :-)

used-to-do-that-stuff-for-a-living-ly y'rs  - steve
-- 
Steve Holden       +44 150 684 7255  +1 800 494 3119
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