Oops... I'll push a repair soon. Thanks!
At Mon, 9 Mar 2015 16:58:41 -0400, Scott Moore wrote: > Hi Matthew, > > Thanks for working on this so quickly! Unfortunately, It looks like there is > a > bug in the fix that causes segfaults when checking impersonator properties on > keyword procedures that are not impersonators. I’ve included a small test > case > below. > > Thanks again, > Scott > > #lang racket > > (define-values (prop:my-prop my-prop? my-prop-accessor) > (make-impersonator-property 'my-prop)) > > (define kwp > (make-keyword-procedure > (λ (kwds kwd-args . other-args) > (printf "Keywords: ~a~n" kwds) > (printf "Keyword arguments: ~a~n" kwd-args) > (printf "Other arguments: ~a~n" other-args)) > (λ args > (printf "Arguments: ~a~n" args)))) > > (my-prop? kwp) > > > On Mar 8, 2015, at 10:12 PM, Matthew Flatt <mfl...@cs.utah.edu> wrote: > > > > I agree that this is a bug --- specific to impersonators that are not > > chaperones --- and I've pushed a repair to the Git repo. > > > > The general repair was to make impersonator-property predicates and > > accessors sensitive to `prop:impersonator-of`. When a structure > > impersoator does not have a particular impersonator property, but its > > structure has the `prop:impersonator-of` property, then the structure > > produced by `prop:impersonator-of` is checked (recursively). That > > change fixes the problem with keyword procedures, because > > `impersonator-procedure` on keyword-acepting procedure is implemented > > through an internal structure type that has `prop:impersonator-of`. > > > > Thanks for the report! > > > > At Fri, 6 Mar 2015 20:04:10 -0500, Scott Moore wrote: > >> Hi, > >> > >> I've run into some strange behavior with the interaction between > >> impersonators and make-keyword-procedure. I expect that when not invoked > >> with keywords, the result of make-keyword-procedure and a lambda with the > >> same form should be equivalent. Instead, they behave differently when > >> impersonated. I have included a small module that demonstrates the issue > >> below. I expect that the two checks at the bottom should succeed. > >> > >> Thanks, > >> Scott > >> > >> #lang racket > >> > >> (require rackunit) > >> > >> (define-values (prop:my-prop my-prop? my-prop-accessor) > >> (make-impersonator-property 'my-prop)) > >> > >> (define (mark-with-my-prop val) > >> (impersonate-procedure > >> val > >> #f > >> prop:my-prop > >> #t)) > >> > >> (define (mark-fun-mkp f) > >> (mark-with-my-prop > >> (make-keyword-procedure > >> (λ (kwds kwd-args . other-args) > >> (keyword-apply f kwds kwd-args other-args)) > >> (λ args > >> (apply f args))))) > >> > >> (define (mark-fun-lambda f) > >> (mark-with-my-prop > >> (λ args > >> (apply f args)))) > >> > >> (define (dummy-impersonator val) > >> (make-keyword-procedure > >> (λ (kwds kwd-args . other-args) > >> (apply values kwd-args other-args)) > >> (λ args > >> (apply values args)))) > >> > >> (define marked-mkp (mark-fun-mkp display)) > >> (define marked-lambda (mark-fun-lambda display)) > >> > >> (check-eq? (my-prop? marked-lambda) (my-prop? marked-mkp)) > >> (check-eq? (my-prop? (impersonate-procedure marked-lambda > >> (dummy-impersonator marked-lambda))) > >> (my-prop? (impersonate-procedure marked-mkp (dummy-impersonator > >> marked-mkp)))) > >> ____________________ > >> Racket Users list: > >> http://lists.racket-lang.org/users ____________________ Racket Users list: http://lists.racket-lang.org/users
