Re: with-syntax return error in Guile, not in Kawa or Racket

[Damien Mattei]

not sure to understand, i admit i'm testing new things for me , i try to
understand macro syntax and all the stuff... reading
 https://www.greghendershott.com/fear-of-macros/index.html
but half (or less) the way.....

do you mean just replacing 'list by #'list ?

i do it and it is still working at least:

(define-syntax $bracket-apply$

  (lambda (stx)

    (syntax-case stx ()

;; a version that pre-compil the infix expression, should be faster;;
scheme@(guile-user)> {#(1 2 3 4 5 6 7 8 9)[6 - 4 : 5 + 2]};;
$bracket-apply$ : parsed-evaluated-args=#<syntax (list (- 6 4) : (+ 5
2))>;; $1 = #(3 4 5 6 7);; scheme@(guile-user)> (define i 5);;
scheme@(guile-user)> {#(1 2 3 4 5 6 7 8 9)[6 - 4 : i + 2]};;
$bracket-apply$ : parsed-evaluated-args=#<syntax (list (- 6 4) : (+ i
2))>;; $2 = #(3 4 5 6 7)
      (($bracket-apply$ container . args-brackets)


       (with-syntax ((parsed-evaluated-args (datum->syntax stx ; #f
                                                           (cons #'list
                                                                 
(optimizer-parse-square-brackets-arguments-lister
(syntax->datum #'args-brackets))))))
                    ;;(display "$bracket-apply$ : parsed-evaluated-args=") 
(display
#'parsed-evaluated-args) (newline)
                
                    #'($bracket-apply$next4list-args container 
parsed-evaluated-args))))))


another strange thing perheaps related to macro is that the compile warns
me always that the optimizer-parse-square-brackets-arguments-lister
procedure is not found:

GNU Guile 3.0.8.99-f3ea8
Copyright (C) 1995-2022 Free Software Foundation, Inc.

Guile comes with ABSOLUTELY NO WARRANTY; for details type `,show w'.
This program is free software, and you are welcome to redistribute it
under certain conditions; type `,show c' for details.

Enter `,help' for help.
scheme@(guile-user)> (use-modules (Scheme+))
;;; note: auto-compilation is enabled, set GUILE_AUTO_COMPILE=0
;;;       or pass the --no-auto-compile argument to disable.
;;; compiling /usr/local/share/guile/site/3.0/Scheme+.scm
;;; note: source file /usr/local/share/guile/site/3.0/for_next_step.scm
;;;       newer than compiled
/Users/mattei/.cache/guile/ccache/3.0-LE-8-4.6/usr/local/share/guile/site/3.0/for_next_step.scm.go
;;; compiling /usr/local/share/guile/site/3.0/for_next_step.scm
;;; compiled
/Users/mattei/.cache/guile/ccache/3.0-LE-8-4.6/usr/local/share/guile/site/3.0/for_next_step.scm.go
;;; note: source file /usr/local/share/guile/site/3.0/growable-vector.scm
;;;       newer than compiled
/Users/mattei/.cache/guile/ccache/3.0-LE-8-4.6/usr/local/share/guile/site/3.0/growable-vector.scm.go
;;; compiling /usr/local/share/guile/site/3.0/growable-vector.scm
;;; growable-vector.scm:149:2: warning: possibly wrong number of arguments
to `vector-copy'
;;; compiled
/Users/mattei/.cache/guile/ccache/3.0-LE-8-4.6/usr/local/share/guile/site/3.0/growable-vector.scm.go
;;; note: source file /usr/local/share/guile/site/3.0/infix-operators.scm
;;;       newer than compiled
/Users/mattei/.cache/guile/ccache/3.0-LE-8-4.6/usr/local/share/guile/site/3.0/infix-operators.scm.go
;;; compiling /usr/local/share/guile/site/3.0/infix-operators.scm
;;; compiled
/Users/mattei/.cache/guile/ccache/3.0-LE-8-4.6/usr/local/share/guile/site/3.0/infix-operators.scm.go
;;; note: source file /usr/local/share/guile/site/3.0/overload.scm
;;;       newer than compiled
/Users/mattei/.cache/guile/ccache/3.0-LE-8-4.6/usr/local/share/guile/site/3.0/overload.scm.go
;;; compiling /usr/local/share/guile/site/3.0/overload.scm
;;; compiled
/Users/mattei/.cache/guile/ccache/3.0-LE-8-4.6/usr/local/share/guile/site/3.0/overload.scm.go
;;; note: source file /usr/local/share/guile/site/3.0/array.scm
;;;       newer than compiled
/Users/mattei/.cache/guile/ccache/3.0-LE-8-4.6/usr/local/share/guile/site/3.0/array.scm.go
;;; compiling /usr/local/share/guile/site/3.0/array.scm
;;; compiled
/Users/mattei/.cache/guile/ccache/3.0-LE-8-4.6/usr/local/share/guile/site/3.0/array.scm.go
;;; WARNING: compilation of /usr/local/share/guile/site/3.0/Scheme+.scm
failed:
;;; *Unbound variable: optimizer-parse-square-brackets-arguments-lister*
scheme@(guile-user)> {v <+ (vector 1 2 3 4)}
scheme@(guile-user)> {v[1 : 3] <- #(-1 -2 -3 -4 -5 -6 -7)[2 : 4]}
scheme@(guile-user)> v
$1 = #(1 -3 -4 4)

but anyway it works 🤔



On Mon, May 6, 2024 at 8:58 PM Maxime Devos <maximedevos@telenet.be> wrote:

> > [...]
>
> >
>
> > That should work, but it's also non-hygienic. For example, it will
>
> > be affected if the user does
>
> >
>
> > (let ((list ...))
>
> >   (call-your-macro ...))
>
> >
>
> >> and since you use #f in the datum->syntax call, it will also strip away
>
> >> all hygiene annotations from the args-brackets, causing problems inside
>
> >> that as well.
>
> >>
>
>
>
> >i changed #f to stx in the macro
>
>
>
> That doesn’t make it hygienic, for the reasons mentioned above.
>
>
>
> syntax (#') / quasisyntax (#`)/ unsyntax (#,)  and unsyntax-splicing (#,@)
> your friend – they behave pretty much the same as their
> quote/quasiquote/... counterparts.
>
>
>
> Hygiene is usually pretty simple – just don’t do sexp things (say,
> quasiquote), do syntax things (quasisyntax) instead, then typically things
> will go well.
>
>
>
> Best regards,
>
> Maxime Devos.
>