Q1) The code below creates two macros. One called `define-foo' which generates
a new identifier and
then defines that to #t. The other, `define-foo/p', generates the same
identifier (lexical issue?)
and another identifier, then "calls" define-foo and then uses both identifiers
in a `define'. When
executed I get this error:
scheme@(guile-user)> (define-foo/p abc)
;;; <stdin>:2:0: warning: possibly unbound variable `wrap-abc'
<unnamed port>:2:0: <unnamed port>:2:0: In procedure module-lookup: Unbound
variable: wrap-abc
What am I doing wrong here?
Q2) Also with respect to the code below. Is there any way to pull the
definitions for stx->str
and gen-id out of the define-syntax body to make them general purpose?
This code being developed under guile-2.2.2.
The code:
(define-syntax define-foo
(lambda (x)
(define (stx->str stx)
(symbol->string (syntax->datum stx)))
(define (gen-id tmpl-id . args)
(datum->syntax
tmpl-id
(string->symbol
(apply string-append
(map (lambda (ss) (if (string? ss) ss (stx->str ss))) args)))))
(syntax-case x ()
((_ name)
(with-syntax ((wrap (gen-id x "wrap-" #'name)))
#'(begin
(define wrap #t)))))))
(define-syntax define-foo/p
(lambda (x)
(define (stx->str stx)
(symbol->string (syntax->datum stx)))
(define (gen-id tmpl-id . args)
(datum->syntax
tmpl-id
(string->symbol
(apply string-append
(map (lambda (ss) (if (string? ss) ss (stx->str ss))) args)))))
(syntax-case x ()
((_ name)
(with-syntax ((wrap (gen-id x "wrap-" #'name))
(rewrap (gen-id x "rewrap-" #'name)))
#'(begin
(define-foo name)
(define rewrap wrap)))))))
;;(define-foo/p abc)
;; expect:
;; (define wrap-abc #t)
;; (define rewrap-abc wrap-abc)
;;(define-foo abc) ;; works (but does not define rewrap-abc
;; expect:
;; (define wrap-abc #t)
Thanks for the help,
Matt
