Do you want to hide the specific types of the job? Presumably to then
define a type JobList = [Job] ?
You can do that with the ExistentialQuantification extension.
type Job = forall k a. Map k a
type JobList = [Job]
??
Note you can't unpack the types k a once you have hidden them. But the
typechecker can use it to ensure some static property.
Also you could use unsafeCoerce to do some casts, but *only if you are
*sure* that things will go OK*.
2012/6/13 Magicloud Magiclouds
Hi, I've forgotten this. This is OK: type Job k a = Map k a And this is OK: {-# LANGUAGE RankNTypes #-} -- or LiberalTypeSynonyms? type Job = forall a. forall k. Map k a
Then how to write it like this? type Job = Map k a -- 竹密岂妨流水过 山高哪阻野云飞
And for G+, please use magiclouds#gmail.com.
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