Re: on second/.go-cached run: ERROR: Unbound variable: for-each - simplified

[Andy Wingo]

Hi Janneke,

On Wed 23 Feb 2011 12:54, Jan Nieuwenhuizen <address@hidden> writes:

> This morning I've spend some time to reduce this problem into
> a single scheme file, see attached.  
>
> Again, here's what happens when I run it twice, starting from
> a clean cache.  
>
> First run
>
>     12:47:07 address@hidden:~/vc/schikkers-list
>     $ rm -rf ~/.cache/guile
>     12:47:10 address@hidden:~/vc/schikkers-list
>     $ ./compile-cache-run-problem.scm 
>     ;;; note: autocompilation is enabled, set GUILE_AUTO_COMPILE=0
>     ;;;       or pass the --no-autocompile argument to disable.
>     ;;; compiling ./compile-cache-run-problem.scm
>     ;;; compiled 
> /home/janneke/.cache/guile/ccache/2.0-0.T-LE-4/home/janneke/vc/schikkers-list/compile-cache-run-problem.scm.go
>     HALLO
>     12:47:16 address@hidden:~/vc/schikkers-list
>
> Second run
>
>     $ ./compile-cache-run-problem.scm 
>     Backtrace:
>     In module/ice-9/boot-9.scm:
>      170: 13 [catch #t #<catch-closure 86895a0> ...]
>     In unknown file:
>        ?: 12 [catch-closure]
>     In module/ice-9/boot-9.scm:
>       62: 11 [call-with-prompt prompt0 ...]
>     In module/ice-9/eval.scm:
>      389: 10 [eval # #]
>     In module/ice-9/boot-9.scm:
>     1864: 9 [save-module-excursion #<procedure 8697c78 at 
> module/ice-9/boot-9.scm:1878:3 ()>]
>     1172: 8 [load "./compile-cache-run-problem.scm" #f]
>     In unknown file:
>        ?: 7 [load-compiled/vm 
> "/home/janneke/.cache/guile/ccache/2.0-0.T-LE-4/home/janneke/vc/schikkers-list/compile-cache-run-problem.scm.go"]
>     In ./compile-cache-run-problem.scm:
>       20: 6 [#<procedure 868a560 ()>]
>     In module/oop/goops.scm:
>     1552: 5 [#<procedure 8afe820 at module/oop/goops.scm:1550:0 (class . 
> initargs)> #]
>     In unknown file:
>        ?: 4 [%initialize-object #<<notation> 8b01010> ()]
>     In module/oop/goops.scm:
>     1552: 3 [#<procedure 8afe820 at module/oop/goops.scm:1550:0 (class . 
> initargs)> #]
>     In ./compile-cache-run-problem.scm:
>       12: 2 [#<procedure 8b04e40 at ./compile-cache-run-problem.scm:10:0 (obj 
> . initargs)> # ...]
>     In module/ice-9/boot-9.scm:
>      115: 1 [#<procedure 85fc4d8 at module/ice-9/boot-9.scm:110:6 (thrown-k . 
> args)> unbound-variable ...]
>     In unknown file:
>        ?: 0 [catch-closure unbound-variable "module-lookup" ...]
>
>     ERROR: In procedure module-lookup:
>     ERROR: Unbound variable: for-each
>     [1]12:47:17 address@hidden:~/vc/schikkers-list
>     $ 

Guile now exhibits the second behavior only, and not the first behavior.
I think the reason is that map and for-each are now implemented in
Scheme, and thus not primitive generics, and srfi-1 doesn't turn them
into generics any more.  Since the duplicates-handler thing is actually
a list or handlers, and you don't mention `last' in the list, no binding
for `for-each' gets imported.

I suspect the difference between first and second runs had to do with
the interaction between srfi-1 and goops, combined with the
loading-order bug that I fixed.  Yuk, right?

Strictly speaking this recent map / srfi-1 / goops change is
incompatible.  But, I hope you'll agree it's for the better; do let us
know if you need some sort of compatibility shim.

Andy
-- 
http://wingolog.org/