exists Existential datatypes holding evidence of constraints
http://github.com/glehel/exists
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BSD-3-Clause licensed by Gábor Lehel
Maintained by
Gábor Lehel This package contains:
Existential datatypes for holding evidence of constraints on types of kind *
and * -> *
;
Type classes for existential datatypes holding evidence of constraints on types of kind *
and * -> *
;
Completely useless existential datatypes holding evidence of no constraint on types of kind *
and * -> *
;
Assorted type class instances for the above;
A type-level combinator for combining constraint constructors.
(Some of these might be better off as separate packages.)
Data.Exists
has most of the important things.
Minimum GHC: 7.4
Changes in 0.2:
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