Hi Anton,
On Mon, Dec 01, 2025 at 10:10:44PM +0100, Anton Idukov wrote:
> Hi, Diogo. As I understand, Crunch is a transpiler from a narrow subset of
> Scheme lang to C 1-to-1,
Yes, and this is why it is so appealing! I already know how to create a
C+crunch program/library with multiple crunch modules.
> so import such code in Scheme back is
> foreign-function-work. emit-wrappers is kinda automation of such.
Right. That is what I would like to have. The final program should only be in
crunch, having no chicken runtime. I want to have chicken just to test the
crunch modules.
So in the previous example I sent, this is the generated wrapper:
;; foo-wrap.scm - created with
;; chicken-crunch -emit-wrappers foo-wrap.scm foo.scm -o foo.c
(module
foo
(foo)
(import (scheme base) (chicken foreign))
(define foo#foo (begin (foreign-lambda integer foo))))
I just don't know how to get a chicken library out of this file (plus the
crunched foo.c). Trying to translate it to .c gives me
% csc -t foo-wrap.scm
Warning: Exported identifier `foo' has not been defined.
Error: module unresolved: foo
May be the generated wrapper isn't correct? How should it look like?
> But the easy way is (crunch ...) form, for example
Yes. But would that make the module be rather a chicken module, right? I want
to have no chicken runtime except in the tests.
> in mine Mandelbrot function
> https://codeberg.org/Corbas/uik/src/branch/main/examples/broth-mod.scm,
> than it is simple imported in main program
> https://codeberg.org/Corbas/uik/src/branch/main/examples/broth.scm . Ok I
> agree, some quirky way of doing C (especially for those who know C well)
I know what you mean :) A while back I got this ps2decoder written in crunch to
to run on a microcontroller: https://github.com/db7/crunch-ps2decoder
It ends up being quite verbose for the task, but it has its charm.
-d
--
> пн, 1 дек. 2025 г. в 19:46, Diogo via Chicken-users <
> [email protected]>:
>
> > Dear list,
> >
> > I'm again trying to understand how the mix CHICKEN+CRUNCH works.
> >
> > My use case is (still)
> > - a program which should be written only in CRUNCH (and C)
> > - a bunch of test cases written in CHICKEN to test the CRUNCH modules.
> >
> > Let's say we have this CRUNCH module:
> >
> > ;; foo.scm
> > (module foo
> > (foo)
> > (import (scheme base)
> > (crunch c))
> > (define (foo)
> > (c-value byte "0xAA"))
> > )
> >
> > And this silly test case:
> >
> > ;; foo-test.scm
> > (import (scheme base)
> > (scheme write)
> > foo)
> > (display (foo))
> > (newline)
> >
> > I know how to compile the CRUNCH module to use in a C program:
> >
> > chicken-crunch foo.scm -o foo.c
> > gcc -I ... -c -o foo.o foo.c
> > and so on
> >
> > But now, I want to import this in a clean way in the test case. I see two
> > flags
> > in chicken-crunch that seem to be for that, but I don't understand them.
> >
> > chicken-crunch -J -emit-wrappers wrap.scm foo.scm
> >
> > The generated files (besides foo.c) are foo.import.scm:
> >
> > (begin
> > (##sys#with-environment
> > (lambda ()
> > (##sys#register-compiled-module
> > 'foo
> > '#f
> > (scheme#list)
> > '((foo . foo#foo))
> > (scheme#list)
> > (scheme#list)
> > (scheme#list))))
> > (if (memq #:crunched ##sys#features)
> > (begin
> > (crunch.compiler#declare-entity 'foo#foo '(procedure () integer)
> > 'foo))))
> >
> > And wrap.scm:
> >
> > (module
> > foo
> > (foo)
> > (import (scheme base) (chicken foreign))
> > (define foo#foo (begin (foreign-lambda integer foo))))
> >
> > // By the way, I had to do a small change in crunch-driver.scm again, to
> > get the
> > // output in wrap.scm (see below)
> >
> > Now, with these 3 files (foo.c, foo.import.scm, wrap.scm), what is the
> > right way
> > to build foo-test.scm with csc?
> >
> > Thanks for your help.
> >
> > Best,
> > -Diogo
> >
> > --
> > The following patch allows me to get some output with -emit-wrappers.
> >
> > Index: crunch-driver.scm
> > ===================================================================
> > --- crunch-driver.scm (revision 45088)
> > +++ crunch-driver.scm (working copy)
> > @@ -58,7 +58,7 @@
> > (define (emit-wrappers out)
> > (lambda (mod exps)
> > (if mod
> > - (emit-scheme-wrappers/module (##sys#module-name mod) exps out)
> > + (emit-scheme-wrappers/module mod exps out)
> > (emit-scheme-wrappers/exported exps out))))
> >
> > (define short-options (string->list "wxvdJ"))
> >
> >
