Danny, This is an issue with the type Any. Typed Racket has to protect all values passed from typed code to untyped code from all possible type-unsound uses. For many kinds of values, this means Typed Racket has to close off pretty much all kinds of uses. In your case, you have a transparent struct. If it were unwrapped, untyped code could inspect it, extract a constructor for its struct type, create an instance with field contents that violate your define-struct: declaration, and pass it back into typed code. You have to be very careful with Any on boundaries, because it has to make a lot of things completely opaque.
Sadly, off the top of my head, I don't have a quick workaround for you. Maybe Sam will have a better suggestion. Carl Eastlund On Fri, Mar 4, 2011 at 4:20 PM, Danny Yoo <[email protected]> wrote: > I'm hitting an error when trying to pass values between typed and > untyped code. I've shrunk the error to the following test code. > Consider three files 'sim-structs', 'sim.rkt', and 'test-sim.rkt'. > sim-structs and sim are written in Typed Racket, and test-sim is > written in regular racket. > > ;; sim-structs.rkt > #lang typed/racket/base > (provide (all-defined-out)) > (define-struct: machine ([env : (Listof Any)])) #:transparent) > (define-struct: toplevel ([vals : (Vectorof Any)]) #:transparent) > > > ;; sim.rkt > #lang typed/racket/base > (require "sim-structs.rkt") > (provide new-machine) > (: new-machine ( -> machine)) > (define (new-machine) > (make-machine (list (make-toplevel (vector 'foobar))))) > > > ;; test-sim.rkt > #lang racket > (require "sim.rkt" "sim-structs.rkt") > (toplevel-vals (first (machine-env (new-machine)))) > > > > When I try to execute test-sim, it fails with the following error: > > > tesla ~/work/js-sicp-5-5 $ /pro/plt/software/racket/5.1/std/bin/racket > test-sim.rkt > contract violation: expected <toplevel?>, given: #<Typed Value: > #(struct:toplevel #(foobar))> > contract on toplevel-vals24 from > (file > /home/dyoo/work/js-sicp-5-5/sim-structs.rkt) > via > (file > /home/dyoo/work/js-sicp-5-5/test-sim.rkt) > blaming > (file /home/dyoo/work/js-sicp-5-5/sim.rkt) > contract: (-> toplevel? (vectorof Any)) > at: /home/dyoo/work/js-sicp-5-5/sim-structs.rkt:11.16 > > === context === > /pro/plt/software/racket/5.1/std/collects/racket/contract/private/blame.rkt:58:0: > raise-blame-error > /home/dyoo/work/js-sicp-5-5/test-sim.rkt: [running body] > > > > It looks as though there's some special "Typed Value" wrapper there > that shouldn't be visible from the untyped test-sim code. Is there a > workaround? > _________________________________________________ > For list-related administrative tasks: > http://lists.racket-lang.org/listinfo/users > > _________________________________________________ For list-related administrative tasks: http://lists.racket-lang.org/listinfo/users
