The latest version of validation is 1.1.3-1.

validation

Version 1 revision 0 uploaded by qfpl.

Package meta

Synopsis
A data-type like Either but with an accumulating Applicative
Description

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 Validation 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. Validation is an example of, "An applicative functor that is not a monad."

Author
Tony Morris <ʇǝu˙sıɹɹoɯʇ@ןןǝʞsɐɥ> <dibblego>, Nick Partridge <nkpart>
Bug reports
https://github.com/qfpl/validation/issues
Category
Data
Copyright
Copyright (C) 2010-2013 Tony Morris, Nick Partridge Copyright (C) 2014,2015 NICTA Limited Copyright (c) 2016,2017, Commonwealth Scientific and Industrial Research Organisation (CSIRO) ABN 41 687 119 230.
Homepage
https://github.com/qfpl/validation
Maintainer
Tony Morris <ʇǝu˙sıɹɹoɯʇ@ןןǝʞsɐɥ> <dibblego>, Nick Partridge <nkpart>, Queensland Functional Programming Lab <oᴉ˙ldɟb@llǝʞsɐɥ>
Package URL
n/a
Stability
n/a

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