The witness package

[Tags:bsd3, library]

A witness is a value that witnesses some sort of constraint on some list of type variables. This library provides support for simple witnesses, that constrain a type variable to a single type, and equality witnesses, that constrain two type variables to be the same type. It also provides classes for representatives, which are values that represent types. See the paper Witnesses and Open Witnesses (


Versions 0.1, 0.2, 0.3,, 0.4
Dependencies base (>=4.7 && <5), constraints, semigroupoids, transformers [details]
License BSD3
Copyright Ashley Yakeley <>
Author Ashley Yakeley <>
Maintainer Ashley Yakeley <>
Stability Unknown
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Uploaded Sun Jun 26 08:08:09 UTC 2016 by AshleyYakeley
Distributions NixOS:0.4
Downloads 670 total (15 in the last 30 days)
0 []
Status Docs available [build log]
Last success reported on 2016-06-26 [all 1 reports]




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