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				|  |  | +# Supported tags and respective `Dockerfile` links
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				|  |  | +
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				|  |  | +- [`latest`, `7.8` (*7.8/Dockerfile*)](https://github.com/darinmorrison/docker-haskell/blob/399ec9abffb3c86d6747d7ab5dc40556d6de9e4b/7.8/Dockerfile)
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				|  |  | +
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				|  |  | +For more information about this image and its history, please see the [relevant
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				|  |  | +manifest file
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				|  |  | +(`library/haskell`)](https://github.com/docker-library/official-images/blob/master/library/haskell)
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				|  |  | +in the [`docker-library/official-images` GitHub
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				|  |  | +repo](https://github.com/docker-library/official-images).
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				|  |  | +
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				|  |  | +# What is Haskell?
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				|  |  | +
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				|  |  | +[Haskell](http://www.haskell.org) is a [lazy](http://en.wikibooks.org/wiki/Haskell/Laziness), functional, statically-typed programming language with advanced type system features such as higher-rank, higher-kinded parametric [polymorphism](http://en.wikibooks.org/wiki/Haskell/Polymorphism), monadic [effects](http://en.wikibooks.org/wiki/Haskell/Understanding_monads/IO), generalized algebraic data types ([GADT](http://en.wikibooks.org/wiki/Haskell/GADT)s), flexible [type classes](http://en.wikibooks.org/wiki/Haskell/Advanced_type_classes), associated [type families](http://en.wikipedia.org/wiki/Type_family), and more.
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				|  |  | +
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				|  |  | +Haskell's [`ghc`](http://www.haskell.org/ghc) is a [portable](https://ghc.haskell.org/trac/ghc/wiki/Platforms), [optimizing](http://benchmarksgame.alioth.debian.org/u64q/haskell.php) compiler  with a foreign-function interface ([FFI](http://en.wikibooks.org/wiki/Haskell/FFI)), an [LLVM backend](https://www.haskell.org/ghc/docs/7.8.3/html/users_guide/code-generators.html), and sophisticated runtime support for [concurrency](http://en.wikibooks.org/wiki/Haskell/Concurrency), explicit/implicit [parallelism](http://community.haskell.org/~simonmar/pcph/), runtime [profiling](http://www.haskell.org/haskellwiki/ThreadScope), etc. Other Haskell tools like [`criterion`](http://www.serpentine.com/criterion/tutorial.html), [`quickcheck`](https://www.fpcomplete.com/user/pbv/an-introduction-to-quickcheck-testing), [`hpc`](http://www.haskell.org/haskellwiki/Haskell_program_coverage#Examples), and [`haddock`](http://en.wikipedia.org/wiki/Haddock_(software)) provide advanced benchmarking, property-based testing, code coverage, and documentation generation.
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				|  |  | +
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				|  |  | +A large number of production-quality Haskell libraries are available from [Hackage](https://hackage.haskell.org). The [`cabal`](https://www.fpcomplete.com/user/simonmichael/how-to-cabal-install) tool fetches packages and builds projects using the Hackage ecosystem.
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				|  |  | +
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				|  |  | +
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				|  |  | +## Contents
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				|  |  | +
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				|  |  | +This image ships a minimal Haskell toolchain with the following packages:
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				|  |  | +
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				|  |  | +* `ghc` 7.8.3
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				|  |  | +* `alex` 3.1.3
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				|  |  | +* `cabal-install` 1.20.0.3
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				|  |  | +* `happy` 1.19.4
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				|  |  | +
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				|  |  | +## Usage
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				|  |  | +
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				|  |  | +* Start an interactive interpreter session with `ghci`:
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				|  |  | +
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				|  |  | +    $ docker run -it --rm haskell:7.8
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				|  |  | +    GHCi, version 7.8.3: http://www.haskell.org/ghc/  :? for help
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				|  |  | +    Loading package ghc-prim ... linking ... done.
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				|  |  | +    Loading package integer-gmp ... linking ... done.
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				|  |  | +    Loading package base ... linking ... done.
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				|  |  | +    Prelude>
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				|  |  | +
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				|  |  | +* Dockerize a [Hackage](http://hackage.haskell.org) app with a Dockerfile inheriting from the base image:
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				|  |  | +
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				|  |  | +    FROM haskell:7.8
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				|  |  | +    RUN cabal update && cabal install MazesOfMonad
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				|  |  | +    VOLUME /root/.MazesOfMonad
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				|  |  | +    ENTRYPOINT ["/root/.cabal/bin/mazesofmonad"]
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				|  |  | +
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				|  |  | +* Iteratively develop then ship a Haskell app with a Dockerfile utilizing the
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				|  |  | +build cache:
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				|  |  | +
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				|  |  | +    FROM haskell:7.8
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				|  |  | +
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				|  |  | +    RUN cabal update
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				|  |  | +
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				|  |  | +    # Add .cabal file
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				|  |  | +    ADD ./server/snap-example.cabal /opt/server/snap-example.cabal
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				|  |  | +
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				|  |  | +    # Docker will cache this command as a layer, freeing us up to
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				|  |  | +    # modify source code without re-installing dependencies
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				|  |  | +    RUN cd /opt/server && cabal install --only-dependencies -j4
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				|  |  | +
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				|  |  | +    # Add and Install Application Code
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				|  |  | +    ADD ./server /opt/server
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				|  |  | +    RUN cd /opt/server && cabal install
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				|  |  | +
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				|  |  | +    # Add installed cabal executables to PATH
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				|  |  | +    ENV PATH /root/.cabal/bin:$PATH
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				|  |  | +
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				|  |  | +    # Default Command for Container
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				|  |  | +    WORKDIR /opt/server
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				|  |  | +    CMD ["snap-example"]
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				|  |  | +
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				|  |  | +## Examples
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				|  |  | +
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				|  |  | +See the application snippet above in more detail in the [example snap application](https://github.com/darinmorrison/docker-haskell/tree/master/examples/7.8.3/snap).
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				|  |  | +
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				|  |  | +# License
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				|  |  | +
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				|  |  | +This image is licensed under the MIT License (see
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				|  |  | +[LICENSE](https://github.com/darinmorrison/docker-haskell/blob/master/LICENSE)),
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				|  |  | +and includes software licensed under the
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				|  |  | +[Glasgow Haskell Compiler License](https://www.haskell.org/ghc/license)
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				|  |  | +(BSD-style).
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				|  |  | +
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				|  |  | +# User Feedback
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				|  |  | +
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				|  |  | +## Issues
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				|  |  | +
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				|  |  | +If you have any problems with or questions about this image, please contact us
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				|  |  | + through a [GitHub issue](https://github.com/darinmorrison/docker-haskell/issues).
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				|  |  | +
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				|  |  | +You can also reach many of the official image maintainers via the
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				|  |  | +`#docker-library` IRC channel on [Freenode](https://freenode.net).
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				|  |  | +
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				|  |  | +## Contributing
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				|  |  | +
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				|  |  | +You are invited to contribute new features, fixes, or updates, large or small;
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				|  |  | +we are always thrilled to receive pull requests, and do our best to process them
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				|  |  | +as fast as we can.
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				|  |  | +
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				|  |  | +Before you start to code, we recommend discussing your plans 
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				|  |  | +through a [GitHub issue](https://github.com/darinmorrison/docker-haskell/issues), especially for more ambitious
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				|  |  | +contributions. This gives other contributors a chance to point you in the right
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				|  |  | +direction, give you feedback on your design, and help you find out if someone
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				|  |  | +else is working on the same thing.
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