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
Dependencies base (>=4.5 && <5) [details]
License GPL-3.0-only
Author Justus Sagemüller
Maintainer jsag@hvl.no
Category Constraints
Home page https://github.com/leftaroundabout/trivial-constraint
Source repo head: git clone git://github.com/leftaroundabout/trivial-constraint.git
Uploaded by leftaroundabout at Mon Jun 3 09:24:04 UTC 2019
Distributions NixOS:0.5.1.0
Downloads 1780 total (138 in the last 30 days)
Rating (no votes yet) [estimated by rule of succession]
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Status Hackage Matrix CI
Docs available [build log]
Last success reported on 2019-06-03 [all 1 reports]

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