The validation package

[ Tags: bsd3, data, library ] [ Propose Tags ]

A data-type like Either but with differing properties and type-class instances.

Library support is provided for this different representation, include lens-related functions for converting between each and abstracting over their similarities.

The AccValidation data type is isomorphic to Either, but has an instance of Applicative that accumulates on the error side. That is to say, if two (or more) errors are encountered, they are appended using a Semigroup operation.

As a consequence of this Applicative instance, there is no corresponding Bind or Monad instance. AccValidation is an example of, "An applicative functor that is not a monad."


Versions 0.3.0, 0.3.1, 0.3.2, 0.3.3, 0.3.4, 0.4.0, 0.4.1, 0.4.2, 0.4.3, 0.5.0, 0.5.1, 0.5.2, 0.5.3, 0.5.4, 0.5.5, 0.6.0
Change log changelog
Dependencies base (>=3 && <5), bifunctors (>=3.0), lens (>=4.0 && <5), mtl (>=2.0 && <2.3), semigroupoids (>=4.0), semigroups (>=0.8), transformers (>=0.3 && <0.6) [details]
License BSD3
Copyright Copyright (c) 2016,2017, Commonwealth Scientific and Industrial Research Organisation (CSIRO) ABN 41 687 119 230.
Author Tony Morris <ʇǝu˙sıɹɹoɯʇ@ןןǝʞsɐɥ> <dibblego>, Nick Partridge <nkpart>
Maintainer Tony Morris <ʇǝu˙sıɹɹoɯʇ@ןןǝʞsɐɥ> <dibblego>, Nick Partridge <nkpart>, Queensland Functional Programming Lab <oᴉ˙ldɟb@llǝʞsɐɥ>
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Source repository head: git clone
Uploaded Wed Oct 11 02:42:28 UTC 2017 by qfpl
Distributions LTSHaskell:0.5.5, NixOS:0.5.5, Stackage:0.6.0, Tumbleweed:0.5.4
Downloads 4151 total (150 in the last 30 days)
Rating 0.0 (0 ratings) [clear rating]
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Status Docs uploaded by user
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