At Thu, 11 Apr 2013 20:14:48 -0400, JP Verkamp wrote: > Thanks for the advice! It's certainly been an interesting journey into > Typed Racket... :) > > Here are the results thus far (for a 256x256 perlin, simplex, and > colored-simplex image). > > Original: > cpu time: 1139 real time: 1134 gc time: 232 > cpu time: 780 real time: 773 gc time: 124 > cpu time: 1950 real time: 2044 gc time: 328 > > Typed: > cpu time: 640 real time: 653 gc time: 110 > cpu time: 546 real time: 542 gc time: 62 > cpu time: 1342 real time: 1364 gc time: 218 > > So it's definitely a good start. > > Unfortunately, there are a few oddities that I'm not sure how to deal with. > > *1) *Which is more idiomatic / easier for Typed Racket to deal with: > > (: mix (Flonum Flonum Flonum -> Flonum)) > (define (mix a b t) > ...) > > (define: (mix [a : Flonum] [b : Flonum] [t : Flonum]) : Flonum > ...) > > Right now, I'm using the former, but I'm not sure I'm happy with it.
I tend to use the former, but both are idiomatic, and TR treats both the same way. > *2)* How can I deal with integer values (specifically 0) to a function with > flonum types? > > Specifically, perlin (and simplex) have the type:\ > > (: perlin > (case-> (Flonum -> Flonum) > (Flonum Flonum -> Flonum) > (Flonum Flonum Flonum -> Flonum))) > > But if I try to do something like this: > > (perlin (* 1.0 (/ 0 256))) > > I get this error: > > Type Checker: No function domains matched in function application: > Domains: Flonum Flonum Flonum > Flonum Flonum > Flonum > Arguments: Zero > > Basically, (* 1.0 (/ 0 256)) is 0, not 0.0. For the timing tests above, I > worked around this with real->double-flonum but that seems suboptimal (they > types are leaking). Is there something I'm missing there? `(* 0 anything)' is `0', this is a special case in Racket's numeric tower. It does make reasoning about types a little tricky, because the normal contagion rules don't apply. `real->double-flonum' or `fl' is the right thing to use here. > *3)* How do I type a color% / bitmap%? > > I tried typing noisy-image-test.rkt, but I kept running into this. I can > use Any, but it seems like objects should be typeable. No luck finding out > how though. Typed Racket currently has limited support for classes and objects. `bitmap%' and `color%' should already have types (in typed/mred), so maybe that's enough for your needs. Better support for classes and objects is in the works. Vincent ____________________ Racket Users list: http://lists.racket-lang.org/users
