name: validation
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.

Validation

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, &quot;An applicative
functor that is not a monad.&quot;

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Package maintainers

For package maintainers and hackage trustees

Candidates
license_spdx: BSD-3-Clause
version: 0.3.4
spec_version: 1.0
download_url: http://hackage.haskell.org/package/validation-0.3.4/validation-0.3.4.tar.gz
home_url: 
                https://github.com/qfpl/validation
              
news_url: https://libraries.io/hackage/validation/versions.atom
date: 2015-01-26
about_resource: NONE
libraries_io_url: https://libraries.io/hackage/validation?number=0.3.4
vcs_tool: git
vcs_repository: https://github.com/system-f/validation
vcs_branch: master
