I have done some work in this area, and my patches are currently sitting on github waiting for comments. (And also some cleanup by me).
I believe that the current version in my pull request will give a static error here. https://github.com/plt/racket/pull/139 On Tue, Sep 18, 2012 at 5:38 PM, Matthias Felleisen <matth...@ccs.neu.edu> wrote: > > +1 > > A flavor of this problem has come up repeatedly, and it will come up again. > We need some fix. > > > > > > On Sep 18, 2012, at 6:28 PM, Ryan Culpepper wrote: > >> Typed Racket should raise an error saying something like "(Setof Any) cannot >> be translated to a contract". Then elaborate in the docs where you discuss >> interaction with untyped code about what types cannot be converted to >> contracts and maybe why. >> >> Ryan >> >> >> On 09/18/2012 06:00 PM, Sam Tobin-Hochstadt wrote: >>> I'm saying that I don't at the moment know how to avoid giving this >>> error, given the current behavior of `set/c`. >>> >>> On Tue, Sep 18, 2012 at 5:57 PM, Robby Findler >>> <ro...@eecs.northwestern.edu> wrote: >>>> Are you saying it is reasonable that a typed racket program should >>>> produce contract constructor errors like that? >>>> >>>> Robby >>>> >>>> On Tue, Sep 18, 2012 at 4:53 PM, Sam Tobin-Hochstadt <sa...@ccs.neu.edu> >>>> wrote: >>>>> The problem here is that `Any` is a special contract which isn't a >>>>> "chaperone contract", and `set/c` requires chaperone contracts. >>>>> >>>>> It's not obvious to me if this can be detected statically, but you can >>>>> work around this by changing `Any` to some other type. >>>>> >>>>> Sam >>>>> >>>>> On Tue, Sep 18, 2012 at 5:44 PM, Tony Garnock-Jones <to...@ccs.neu.edu> >>>>> wrote: >>>>>> Hi all, >>>>>> >>>>>> What could I be doing wrong here? >>>>>> >>>>>> #lang typed/racket >>>>>> (provide (struct-out foo)) >>>>>> (struct: foo ([bar : (Setof Any)])) >>>>>> >>>>>> Racket 5.3.0.24 complains about it ("racket problem.rkt"): >>>>>> >>>>>> set/c: contract violation >>>>>> expected: chaperone-contract? >>>>>> given: #<make-contract> >>>>>> context...: >>>>>> /Users/tonyg/src/racket-typed-matrix/problem.rkt: [running body] >>>>>> >>>>>> The complaint vanishes if I comment out the provide, remove the bar >>>>>> field, or change the bar field's type to Any/Integer/etc. >>>>>> >>>>>> Tony >>>>>> ____________________ >>>>>> Racket Users list: >>>>>> http://lists.racket-lang.org/users >>>>> >>>>> >>>>> >>>>> -- >>>>> sam th >>>>> sa...@ccs.neu.edu >>>>> ____________________ >>>>> Racket Users list: >>>>> http://lists.racket-lang.org/users >>> >>> >>> >> >> ____________________ >> Racket Users list: >> http://lists.racket-lang.org/users > > > ____________________ > Racket Users list: > http://lists.racket-lang.org/users ____________________ Racket Users list: http://lists.racket-lang.org/users
