[Lightning] Bootstrapping

[Ludovic Courtès]

Hi,

Ian Grant <address@hidden>
skribis:

> ML working under Guile. Moscow ML is really light-weight when compared
> with Guile. My machine takes 42 minutes (no, really, I timed it!)  to
> byte-compile just ice9-pp.go. By comparison, the whole Moscow ML
> autoconf/build cycle takes less than 50s.

(You must be referring to psyntax-pp.scm.)

What language is Moscow ML implemented in?

Guile is bootstrapped from C: it doesn’t need a previous version of
itself or another Scheme implementation to build.  It has an interpreter
written in C.  During bootstrap, that interpreter runs the compiler to
build the final interpreter, ice-9/eval.scm.  From there we build the
rest of the compiler, which includes the macro expander, psyntax.  At
some point down the road, the compiler has been compiled to bytecode, so
things get significantly faster.

It’s a trade-off: this process is CPU-intensive, but it makes sure Guile
can always be built easily.

Ludo’.