trivial-constraint: Constraints that any type, resp. no type fulfills

[ constraints, gpl, library ] [ Propose Tags ]

Since GHC 7.4, constraints are first-class: we have the constraint kind, and thus type-classes have a kind such as * -> Constraint.

These can be used as parameters to data types. They also can be combined quite nicely,

type NewConstraint a = (Constraint1 a, Constraint2 a)

however you always need to start with a plain old type class when building constraints.

This library provides a type class that is not really a constraint at all, so you can "start from zero" with building up a custom constraint. Also its opposite (a constraint that no type can ever fulfill).

Versions [faq] 0.1.0.0, 0.2.0.0, 0.3.0.0, 0.4.0.0, 0.5.0.0, 0.5.1.0, 0.6.0.0
Dependencies base (>=4.5 && <5) [details]
License GPL-3.0-only
Author Justus Sagemüller
Maintainer sagemueller@geo.uni-koeln.de
Revised Revision 1 made by leftaroundabout at Fri Feb 27 12:16:39 UTC 2015
Category Constraints
Home page https://github.com/leftaroundabout/trivial-constraint
Uploaded by leftaroundabout at Tue Jun 3 15:43:16 UTC 2014
Distributions NixOS:0.6.0.0
Downloads 3217 total (267 in the last 30 days)
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Status Hackage Matrix CI
Docs available [build log]
Successful builds reported [all 1 reports]

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