[sorry for not responding earlier] On Fri, Nov 9, 2012 at 11:32 AM, Ray Racine <ray.rac...@gmail.com> wrote: > I did poke around a bit at this with my morning coffee and I'd say it is not > necessarily intuitively obvious to the casual observer on how to go from the > internal "type" representation constructed via Class and Instance to a > usable type predicate accepted in a base-env.rkt type declaration. > > Example of attempting to type spawn-node-supervise-place-at which returns > (values (Instanceof remote-node%) (Instanceof remote-connection%)). > > Seeking to do something along the lines of this: > > [spawn-node-supervise-place-at (->key -String -Module-Path Sym > #:listen-port -NonNegFixnum #f > #:initial-message Univ #f > #:racket-path -Path #f > #:ssh-bin-path -Path #f > #:distributed-launch-path (-opt -Path) > #f > #:restart-on-exit Univ #f > #:place-name (-opt Sym) #f > #:thunk -Boolean #f > (-values (list (-inst remote-node%) > (-inst > remote-connection%))))]
This is mostly right, except for the `(-inst ...)` parts. The argument to `-inst` (assuming you've defined it as an abbreviation for `make-Instance`) should be something created with `make-Class`. You seem to be providing the names of actual Racket classes. > With the companion decl along the lines of thus: > > [remote-connection% (make-pred-ty (make-Class '(...)'(...)'(...)))] `make-pred-ty` is for the type of functions like `number?`. Instead, `remote-connection%`, which is a class, should have a type that's just produced by `make-Class`. -- sam th sa...@ccs.neu.edu ____________________ Racket Users list: http://lists.racket-lang.org/users
