On Jul 27, 2014, at 1:37 PM, Roman Klochkov <[email protected]> wrote:
> I looked into > https://github.com/qerub/rackjure/blob/master/rackjure/lambda-reader.rkt > As far as I understand, reader-proce returns #'(lambda ...) for #λ(...). > But, according to http://docs.racket-lang.org/reference/reader-procs.html it > should return (datum->syntax #f '(lambda ...)) > Maybe, this is the source of the error No, it’s actually a good thing that it returns #’(lambda …) because I want the lambda to be bound to the lambda from racket/base no matter what bindings there might be in the file it’s used in. That’s one great thing about hygienic macros and syntax-objects. For example this works fine: #lang rackjure (require rackunit) (define lambda "whatever") (check-equal? (map #λ(+ % %2) '(1 2 3) '(1 2 3)) '(2 4 6)) If it were (datum->syntax #f ‘(lambda …) it wouldn’t work. That’s why it’s #’(lambda …) instead of (datum->syntax #f '(lambda …)). > > Sun, 27 Jul 2014 12:21:36 -0400 от "Alexander D. Knauth" > <[email protected]>: >> I just tried to try it and see if it worked, when I realized that it won’t >> work because I can’t use quote-syntax. >> >> Is there any way to get around that? And would it even work anyway? >> On Jul 27, 2014, at 6:59 AM, Roman Klochkov < [email protected] > wrote: >>> Maybe via " Cross-Phase Persistent Module Declarations" >>> http://docs.racket-lang.org/reference/syntax-model.html#%28part._cross-phase._persistent-grammar%29 >>> ? >>> >>> >>> Thu, 24 Jul 2014 21:24:20 -0400 от "Alexander D. Knauth" < >>> [email protected] >: >>>> How can I make an identifier that will have a certain binding no matter >>>> what phase level it's referenced at? >>>> >>>> For example if I’m making a reader extension that will produce a lambda >>>> expression, how do I make it so that the lambda expression will be able to >>>> exist at any phase level? >>>> >>>> For example this program using #lang rackjure doesn’t work: >>>> #lang rackjure >>>> (require (for-meta 1 racket/base) >>>> (for-meta 2 racket/base) >>>> (for-meta 3 racket/base) >>>> (for-meta 4 racket/base) >>>> ) >>>> >>>> >>>> #λ(* 2 %) ; works, produces approx. (lambda (%) (* 2 %)) >>>> (begin-for-syntax >>>> (begin-for-syntax >>>> #λ(* 2 %) ; lambda: unbound identifier at phase 2; >>>> ; ; also, no #%app syntax transformer is bound in: lambda >>>> )) >>>> >>>> Is there any way to construct an identifier that would be bound to lambda >>>> from racket/base no matter what phase level it’s used in? >>>> >>>> >>>> ____________________ >>>> Racket Users list: >>>> http://lists.racket-lang.org/users >>>> >>> >>> >>> -- >>> Roman Klochkov > > > -- > Roman Klochkov
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