bug#78831: [PATCH 1/2] language/bf: rewire compiling to scheme

Trying to compile bf to scheme fails with an impressive backtrace:

"In ice-9/boot-9.scm:
  1752:10 13 (with-exception-handler _ _ #:unwind? _ # _)
In unknown file:
          12 (apply-smob/0 #<thunk 7f2594f5d000>)
In ice-9/boot-9.scm:
    724:2 11 (call-with-prompt _ _ #<procedure default-prompt-handle=E2=80=
=A6>)
In ice-9/eval.scm:
    619:8 10 (_ #(#(#<directory (guile-user) 7f2594f12c80>)))
In ice-9/boot-9.scm:
   2836:4  9 (save-module-excursion _)
  4388:12  8 (_)
In /home/[...]/bf2scheme.scm:
     2:15  7 (_)
In system/base/compile.scm:
   307:16  6 (read-and-compile #<input: string 7f25a2ef57e0> #:from _ =E2=
=80=A6)
   278:13  5 (lp _)
   278:13  4 (lp _)
   278:13  3 (lp _)
   278:13  2 (lp _)
    275:6  1 (lp _)
   244:17  0 (next-pass _ _ _ _ _)

system/base/compile.scm:244:17: In procedure next-pass:
no way to compile #<<language> name: brainfuck title: "Brainfuck" reader: #=
<procedure 7f2592825650 at language/brainfuck/spec.scm:42:16 (port env)> pr=
inter: #<procedure write (_ #:optional _)> parser: #f compilers: ((tree-il =
. #<procedure compile-tree-il (exp env opts)>) (scheme . #<procedure compil=
e-scheme (exp env opts)>)) decompilers: () evaluator: #f joiner: #f for-hum=
ans?: #t make-default-environment: #<procedure make-fresh-user-module ()> l=
owerer: #f analyzer: #f compiler-chooser: #<procedure choose-compiler (comp=
ilers optimization-level opts)>> "to" #<<language> name: scheme title: "Sch=
eme" reader: #<procedure 7f2592780650 at language/scheme/spec.scm:34:16 (po=
rt env)> printer: #<procedure write (_ #:optional _)> parser: #f compilers:=
 ((tree-il . #<procedure compile-tree-il (x e opts)>)) decompilers: ((tree-=
il . #<procedure decompile-tree-il (e env opts)>)) evaluator: #<procedure 7=
f2592780660 at language/scheme/spec.scm:45:16 (x module)> joiner: #f for-hu=
mans?: #t make-default-environment: #<procedure 7f2592780670 at language/sc=
heme/spec.scm:48:16 ()> lowerer: #f analyzer: #f compiler-chooser: #f>"

It turns out the compiler for bf is hardwired to compile-tree-il. Make
it possible to choose compile-scheme too.
---
 module/language/brainfuck/spec.scm | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/module/language/brainfuck/spec.scm b/module/language/brainfuck=
/spec.scm
index ca488b916..5827c95f4 100644
--- a/module/language/brainfuck/spec.scm
+++ b/module/language/brainfuck/spec.scm
@@ -35,7 +35,9 @@
 ; language.
=20
 (define (choose-compiler compilers optimization-level opts)
-  (cons 'tree-il compile-tree-il))
+  (if (eq? (language-name compilers) 'scheme)
+    (cons 'scheme compile-scheme)
+    (cons 'tree-il compile-tree-il)))
=20
 (define-language brainfuck
   #:title	"Brainfuck"
--=20
2.49.0