Recursive define-syntax

[Philippe de Rochambeau <phiroc@free.fr>]

Hello,

the following procedure, excerpted from « A Pamphlet Against R » 

(define (dim m)
 (match m
   ((first . rest)
     `(,(length m) . ,(dim first)))
    (_
      '())))

… causes Kawa to display the following error message:

/dev/tty:6:5: unrecognized pattern operator first


I tried rewriting the dim procedure using define-syntax:


(define m0 '((1 2 3 4)(0 4 5 8)(0 0 7 6)))

(define-syntax dim 
    (lambda (m)
        (syntax-case m ()
            ((_ frst . rst)
                #`(#,(length m) . #,(dim first)))
            (_
                '()))))
    
…but to no avail:

matrix1.scm:7:17: duplicated pattern variable frst
matrix1.scm:7:13: duplicated pattern variable rst
matrix1.scm:7:17: duplicated pattern variable frst
matrix1.scm:7:13: duplicated pattern variable rst
…

Are recursive « syntaxes »  not possible in Kawa?

Many thanks.

Philippe