# `invariant` [![Hackage](https://img.shields.io/hackage/v/invariant.svg)][Hackage: invariant] [![Hackage Dependencies](https://img.shields.io/hackage-deps/v/invariant.svg)](http://packdeps.haskellers.com/reverse/invariant) [![Haskell Programming Language](https://img.shields.io/badge/language-Haskell-blue.svg)][Haskell.org] [![BSD3 License](http://img.shields.io/badge/license-BSD3-brightgreen.svg)][tl;dr Legal: BSD3] [![Build](https://img.shields.io/travis/nfrisby/invariant-functors.svg)](https://travis-ci.org/nfrisby/invariant-functors) [Hackage: invariant]: http://hackage.haskell.org/package/invariant "invariant package on Hackage" [Haskell.org]: http://www.haskell.org "The Haskell Programming Language" [tl;dr Legal: BSD3]: https://tldrlegal.com/license/bsd-3-clause-license-%28revised%29 "BSD 3-Clause License (Revised)" Haskell98 invariant functors