hello,
how do i access the pattern variable var at compile time (phase 1?)
additional to an answer, could you point me to the right part of the
documentation? i really couldn't find it.
#lang racket
(define inp (open-input-string "12+34"))
(define-syntax (terminal stx)
(syntax-case stx ()
((_ name rx)
(if (pregexp? (syntax->datum #'rx))
#'(define (name)
(regexp-try-match rx inp))
#'(error "Pregexp expected.")))))
(define-syntax (prod stx)
(syntax-case stx ()
((_ prod-name (name var))
(cond ((procedure? (syntax->datum #'var)) #'1)
((procedure? #'var) #'2)
((procedure? 'var) #'2)
((procedure? #''var) #'3)
((procedure? #''var) #'4)
((procedure? (syntax 'var)) #'5)
((pregexp? #'var) #'0)
(else #'(raise-syntax-error 'PROD-ARGUMENTS "Pregexp oder
Procedure expected."))))))
(terminal digit #px"\\d")
(prod term (op1 digit))
thanks for your help! :-)
--
You received this message because you are subscribed to the Google Groups
"Racket Users" group.
To unsubscribe from this group and stop receiving emails from it, send an email
to racket-users+unsubscr...@googlegroups.com.
For more options, visit https://groups.google.com/d/optout.
