unrecognized pattern operator list

Damien Mattei damien.mattei@gmail.com
Tue Oct 10 05:33:08 GMT 2023


i use 'match' for Kawa like this in my code, i haven't test it yet but
i suppose it is ok ,having done multiple test in the Kawa REPL :

(match (list index1-or-keyword-eval-pos index2-or-keyword-eval-pos)

     ;;  {a <+ (make-vector 7 0)}
     ;; '#(0 0 0 0 0 0 0)
     ;; > {a[$ $] <- #(1 2 3)}
     ;; > a
     ;; '#(1 2 3 0 0 0 0)
                    ;((list (== slice) (== slice))
     ([s1 s2] #!if (and (equal? s1 slice) (equal? s2 slice))
      (container-copy! container-eval
               0
               expr-eval)
      container-eval  ;; returning a value allow the chaining : {T[3 5
6] <- A[4 2 3] <- T[7 2 4]}
      )

     ;;  {s <+ (string-append "abcdefgh")}
     ;; "abcdefgh"
     ;; > {s[3 $] <- "zob"}
     ;; > s
     ;; "abczobgh"
     ;; >
     ([i1 s] #!if (equal? s slice)
      (container-copy! container-eval
               i1
               expr-eval)
      container-eval  ;; returning a value allow the chaining : {T[3 5
6] <- A[4 2 3] <- T[7 2 4]}
      )

     ([s i2] #!if (equal? s slice)
      (container-copy! container-eval
               0
               expr-eval
               0
               i2)
      container-eval  ;; returning a value allow the chaining : {T[3 5
6] <- A[4 2 3] <- T[7 2 4]}
      )

     ([i1 i2]
      (cond ((vector? container-eval)  ;; normal case
         (function-array-n-dim-set! container-eval expr-eval (reverse
(list i1 i2))))
        ((array? container-eval)
         ;;(display "assignment.* : 2 args ,array case :
container-eval = ") (display container-eval) (newline)
         (array-set! container-eval index1-or-keyword-eval
index2-or-keyword-eval expr-eval))

        (else ;; overloaded
         (define args-lst (list container-eval i1 i2))
         (define setter! (find-setter-for-overloaded-square-brackets args-lst))
         (setter! container-eval i1 i2 expr-eval)))
      expr-eval) ;; returning a value allow the chaining : {T[3 2] <-
A[4] <- T[2 4]}

     ) ;; end match

i can not find another way than:

#!if (and (equal? s1 slice) (equal? s2 slice)

to test equality to '($ $) or (list slice slice) , that does not look
like a pattern and i could have use 'cond' instead of 'match' as there
is little gain in syntax here.

On Mon, Oct 9, 2023 at 11:07 PM Damien Mattei <damien.mattei@gmail.com> wrote:
>
> GRASP ,amazing code , would be wonderful for teaching.
>
> On Mon, Oct 9, 2023 at 10:26 PM Panicz Maciej Godek
> <godek.maciek@gmail.com> wrote:
> >
> > For what it's worth, I wrote my own implementation of match for Kawa and use it in GRASP:
> >
> > https://github.com/panicz/grasp/blob/main/src/language/match.scm
> >
> > It is derived from the now withdrawn SRFI-200 document that I submitted at some point:
> >
> > https://srfi.schemers.org/srfi-200/srfi-200.html
> >
> > (it contains a fairly detailed description of the implementation of the match macro, both in syntax-case and syntax-rules)
> >
> > Anyway, it doesn't seem to be causing any conflicts with Kawa's built-in match, so you cloud try adapting it to your taste.
> >
> > pon., 9 paź 2023 o 22:18 Damien Mattei via Kawa <kawa@sourceware.org> napisał(a):
> >>
> >>      one of problem is coming from the special syntax of kawa that use
> >> [ ] where others scheme don't and incompatible with SRFI 105, this
> >> limits some use.
> >> like: in type[] or match with patterns looking like ([_ y] ...
> >> this would be a good idea to have an option in Kawa that allow
> >> replacing those [ ] by normal ( ) or even be compatible with the 2
> >> syntaxes should be possible
> >>
> >> in my case i dislike 'match form and do not using typing in scheme
> >> when available so this not a big problem in my codes but for now i do
> >> not know how to modify the SRFI-105 reader for be compatible. It is
> >> also possible to parse it with SRFI 105 and after modify again the
> >> code to set back the transformed [] in () again in [] in 'match and
> >> type[]  ....
> >>
> >>
> >> On Mon, Oct 9, 2023 at 4:48 PM Damien Mattei <damien.mattei@gmail.com> wrote:
> >> >
> >> > hello,
> >> >
> >> > in this code belonging from Guile and Racket version:
> >> >
> >> > (match (list index1-or-keyword-eval-pos index2-or-keyword-eval-pos
> >> > index3-or-keyword-or-step-eval-pos)
> >> >
> >> >
> >> >
> >> >
> >> >      ;;  {a <+ (make-vector 7 0)}
> >> >      ;; '#(0 0 0 0 0 0 0)
> >> >      ;; > {a[$ $] <- #(1 2 3)}
> >> >      ;; > a
> >> >      ;; '#(1 2 3 0 0 0 0)
> >> >      ((list (== slice) (== slice))
> >> >       (container-copy! container-eval
> >> >                0
> >> >                expr-eval)
> >> >
> >> > i have this error:
> >> > unrecognized pattern operator list near ((list (== slice) i2 (== slice))
> >> > slice is defined like that:
> >> >
> >> > (define $ '$)
> >> > (define slice $)
> >> >
> >> > what is the equivalent syntax for kawa?
> >> >
> >> > damien


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