view tests/type_classMod.ur @ 297:59dc042629b9

pquery working with all four types of columns
author Adam Chlipala <adamc@hcoop.net>
date Sun, 07 Sep 2008 13:29:01 -0400
parents 71bafe66dbe1
children
line wrap: on
line source
structure M = struct
        structure N = struct
                class c t = t
                val string_c : c string = "Hi"
        end
end

val c : t :: Type -> M.N.c t -> t =
        fn t :: Type => fn pf : M.N.c t => pf
val hi = c [string] _

val bool_c : M.N.c bool = True
val true = c [bool] _
val hi = c [string] _

con c = M.N.c
val int_c : c int = 0
val zero = c [int] _