Re: (debug-options 'full) is broken

[Andy Wingo]

On Tue 09 Jun 2009 21:27, Mark H Weaver <address@hidden> writes:

> According to node "User level options interfaces" of api-options.texi,
> (debug-options 'full) should print a list of options, but it fails
> with "ERROR: unbound variable: option-name".  The other options
> interfaces (eval-options, read-options, print-options, traps) are
> broken as well.
>
> The problem is here, in boot-9.scm:
>
> (defmacro define-option-interface (option-group)
>   (let* ((option-name car)
>        (option-value cadr)
>        (option-documentation caddr)
>
>        ;; Below follow the macros defining the run-time option interfaces.
>
>        (make-options (lambda (interface)
>                        `(lambda args
>                           (cond ((null? args) (,interface))
>                                 ((list? (car args))
>                                  (,interface (car args)) (,interface))
>                                 (else (for-each
>                                          (lambda (option)
>                                            (display (option-name option))
>                                            (if (< (string-length
>                                                    (symbol->string 
> (option-name option)))
>                                                   8)
>                                                (display #\tab))
>                                            (display #\tab)
>                                            (display (option-value option))
>                                            (display #\tab)
>                                            (display (option-documentation 
> option))
>                                            (newline))
>                                          (,interface #t)))))))
> [...etc...]
>
> How was this supposed to work?  How were the local bindings of
> option-name, option-value, and option-documentation supposed to be
> referenced from within the expansion of this non-hygienic macro?

Umm... Oops :) See, these things used to be "memoizing macros", the
thing that Guile's old defmacros were built on. I translated them to
defmacros, but, um, not very well, apparently ;-)

I'll see if I can push a fix. BTW I pushed something that might affect
the stack overflow issue, can you give that a try? I have one report of
it working where it didn't use to work.

Cheers,

Andy
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