Re: [Chicken-users] hygienic branch (progress report, sort of)

[Jim Ursetto]

Possible bug?  Despite lambda being renamed in define's definition
in expand.scm, it seems to break hygiene:

(let ((lambda 3)) (define (foo x) x))

Error: unbound variable: x

        Call history:

        <syntax>        (let280 ((foo (##core#undefined)))
                        (##core#set! foo (lambda278 (x) x)))
        <syntax>        (begin282 (##core#set! foo (lambda278 (x) x)))
        <syntax>        (##core#set! foo (lambda278 (x) x))
        <syntax>        (lambda278 (x) x)

Yet renaming works in general:

#;3> (##sys#extend-macro-environment 'def '()
       (##sys#er-transformer (lambda (f r c) `(,(r 'define) (foo) 3))))
#;4> ,x (def)
(##core#set! foo (lambda () 3))
#;4> (let ((define 0)) (def) (foo))         ;; ok
3
#;5> (let ((lambda 0)) (def) (foo))         ;; fail
Error: illegal non-atomic object: ()


However if we manually do the core expansion of
(define (foo) ...) => (define foo (lambda () ...))
then the result is correct:

#;6> (##sys#extend-macro-environment 'def '()
       (##sys#er-transformer (lambda (f r c)
         `(,(r 'define) foo (,(r 'lambda) () 3)))))
#;7> ,x (def)
(##core#set! foo (lambda () 3))
#;7> (let ((lambda 0)) (def) (foo))         ;; ok
3


Weird.


On 5/14/08, felix winkelmann <address@hidden> wrote:
> Please feel free to ask questions and please report any bugs you'll
> find. I will update the manual and announce it once I'm ready. You
> can look in tests/module-tests.scm and of course the sources for first
> hints at how things work.