Re: [racket-dev] splicing-syntax-parameterize and syntax-parameter-value
Interesting problem. I almost gave up, but I think I've sorted it out --- repair pushed. At Thu, 29 Nov 2012 18:20:18 -0500 (EST), J. Ian Johnson wrote: Simpler example: (require racket/splicing racket/stxparam) (define-syntax-parameter f #f) (define x 0) ;; 0 (syntax-parameterize ([f (make-rename-transformer #'x)]) (splicing-syntax-parameterize ([f (syntax-parameter-value #'f)]) f)) ;; 0 (splicing-syntax-parameterize ([f (make-rename-transformer #'x)]) (syntax-parameterize ([f (syntax-parameter-value #'f)]) f)) ;; error (splicing-syntax-parameterize ([f (make-rename-transformer #'x)]) (splicing-syntax-parameterize ([f (syntax-parameter-value #'f)]) f)) stdin::334: f: bad syntax in: f context...: /home/ianj/racket/collects/racket/splicing.rkt:224:0 /home/ianj/racket/collects/racket/splicing.rkt:177:0 /home/ianj/racket/collects/racket/splicing.rkt:224:0 /home/ianj/racket/collects/racket/splicing.rkt:177:0 /home/ianj/racket/collects/racket/private/misc.rkt:87:7 -Ian - Original Message - From: J. Ian Johnson i...@ccs.neu.edu To: dev dev@racket-lang.org Sent: Thursday, November 29, 2012 4:01:09 PM GMT -05:00 US/Canada Eastern Subject: [racket-dev] splicing-syntax-parameterize and syntax-parameter-value (require racket/stxparam racket/splicing) (define-syntax-parameter f #f) (splicing-syntax-parameterize ([f #t]) (begin-for-syntax (printf ~a~% (syntax-parameter-value #'f))) (void)) This prints #f. If I instead add a macro indirection (define-syntax (blah stx) (syntax-case stx () [(_ f) (printf ~a~% (syntax-parameter-value #'f)) #'(void)])) Then (splicing-syntax-parameterize ([f #t]) (blah f) (void)) prints #t This is messing up some of my syntax parameters that build their definitions from the existing value in the parameter. Why does the first program have this behavior? This feels bug-like to me. -Ian _ Racket Developers list: http://lists.racket-lang.org/dev
Re: [racket-dev] splicing-syntax-parameterize and syntax-parameter-value
Simpler example: (require racket/splicing racket/stxparam) (define-syntax-parameter f #f) (define x 0) ;; 0 (syntax-parameterize ([f (make-rename-transformer #'x)]) (splicing-syntax-parameterize ([f (syntax-parameter-value #'f)]) f)) ;; 0 (splicing-syntax-parameterize ([f (make-rename-transformer #'x)]) (syntax-parameterize ([f (syntax-parameter-value #'f)]) f)) ;; error (splicing-syntax-parameterize ([f (make-rename-transformer #'x)]) (splicing-syntax-parameterize ([f (syntax-parameter-value #'f)]) f)) stdin::334: f: bad syntax in: f context...: /home/ianj/racket/collects/racket/splicing.rkt:224:0 /home/ianj/racket/collects/racket/splicing.rkt:177:0 /home/ianj/racket/collects/racket/splicing.rkt:224:0 /home/ianj/racket/collects/racket/splicing.rkt:177:0 /home/ianj/racket/collects/racket/private/misc.rkt:87:7 -Ian - Original Message - From: J. Ian Johnson i...@ccs.neu.edu To: dev dev@racket-lang.org Sent: Thursday, November 29, 2012 4:01:09 PM GMT -05:00 US/Canada Eastern Subject: [racket-dev] splicing-syntax-parameterize and syntax-parameter-value (require racket/stxparam racket/splicing) (define-syntax-parameter f #f) (splicing-syntax-parameterize ([f #t]) (begin-for-syntax (printf ~a~% (syntax-parameter-value #'f))) (void)) This prints #f. If I instead add a macro indirection (define-syntax (blah stx) (syntax-case stx () [(_ f) (printf ~a~% (syntax-parameter-value #'f)) #'(void)])) Then (splicing-syntax-parameterize ([f #t]) (blah f) (void)) prints #t This is messing up some of my syntax parameters that build their definitions from the existing value in the parameter. Why does the first program have this behavior? This feels bug-like to me. -Ian _ Racket Developers list: http://lists.racket-lang.org/dev _ Racket Developers list: http://lists.racket-lang.org/dev
