On 08-10-2010, Jake Donham <j...@donham.org> wrote: > On Fri, Oct 8, 2010 at 10:13 AM, Sylvain Le Gall <sylv...@le-gall.net> wrote: >> This code doesn't compile because I see no way to explain that F.kind is >> included into plugin_kind. > > As you have written it, F.kind is of course completely abstract. I am > not sure where you need F.kind to be a strict subtype of plugin_kind, > but you could say type kind = plugin_kind (this seems a bit useless > however). > > I don't think there is a way to use subtyping implicitly when applying > a functor, but you can always do it explicitly by interposing a module > of signature PLUGIN_FAMILY which embeds the specific kind in > plugin_kind and passes the other components through. > > You could also have a general and a specific type in the plugin > signature, and use the general one for general operations (e.g. help) > but the specific one wherever that is needed. I am not sure I > understand what you're trying to achieve however. >
My goal is that the compiler prevents me to do Build.act pkg.plugin_install -> because plugin_install is of type [`Install] plugin and Build.act needs [`Build] plugin but allow me to do help pkg.plugin_install -> because help needs [`Build | `Install] plugin. But maybe I am missing something here and try to overengineer something simple. Regards, Sylvain Le Gall _______________________________________________ Caml-list mailing list. Subscription management: http://yquem.inria.fr/cgi-bin/mailman/listinfo/caml-list Archives: http://caml.inria.fr Beginner's list: http://groups.yahoo.com/group/ocaml_beginners Bug reports: http://caml.inria.fr/bin/caml-bugs
