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A Haskell re-implementation of the Nix expression language
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benchmarks Reformat all sources with Brittany, to restore consistency Mar 17, 2019
data Bump C++ Nix submodule Mar 9, 2019
doc Add the C++ parser as documentation Jul 4, 2014
ghcjs Try to integrate hnix-store-core into hnix-store ghcjs build Mar 22, 2019
tests Builtins: add builtins.concatMap Apr 1, 2019
.gitignore Less than test (#461) Mar 10, 2019
.travis.yml Remove the caching build from the Travis build matrix Mar 10, 2019
CODEOWNERS Add a CODEOWNERS file, to automate review assignments Apr 6, 2019
Dockerfile Modify the Docker build to use as well May 13, 2018
LICENSE Change LICENSE to BSD3 Dec 19, 2016
Makefile Merge {build,shell,default}.nix into default.nix Jan 28, 2018 Begin work on harmonizing the two different value representations Mar 18, 2019 PRETTY_TESTS is assumed to be an integer, not yes/no Mar 9, 2019
Setup.hs Setup cabal file, fix all warnings Jul 1, 2014
brittany.yaml allow passing extra flags like -K or -j1 Aug 6, 2018
default.nix Simplify Standard.hs further by creating Nix.Utils.Fix1 Mar 23, 2019
hnix.cabal Bump version to 0.6.1 Apr 19, 2019
hydra.json Fix declarative hydra config Nov 17, 2018
jobsets.nix Try to enable hydra testing of "pending" branch Nov 18, 2018
release.nix Fix release.nix Mar 10, 2019
shell.nix Expose a haskell package set, don't use inNixStore for shell Mar 10, 2019


Build Status Chat (Hackage Matrix Builder)

Haskell parser, evaluator and type checker for the Nix language.


Nix is installed and in your $PATH. This is so that nix-store can be used for interacting with store paths, until hnix-store is ready.

Getting Started

$ git clone --recursive
$ cd hnix
$ nix-shell
$ cabal configure --enable-tests
$ cabal build
$ cabal test
# To run all of the tests, which takes up to a minute:
$ env ALL_TESTS=yes cabal test
# To run only specific tests (see `tests/Main.hs` for a list)
$ env NIXPKGS_TESTS=yes PRETTY_TESTS=1 cabal test
$ ./dist/build/hnix/hnix --help

Building a Docker container

If you don't have Nix installed, or you'd just like to play around with hnix completely separately from your main system, you can build a Docker container:

$ docker build -t hnix .
$ docker run hnix hnix --eval --expr '1 + 2'

# In order to refer to files under the current directory:
$ docker run -v $PWD/:/tmp/build run hnix hnix default.nix

Building with full debug info

To build hnix for debugging, and with full tracing output and stack traces, use:

$ nix-shell
$ cabal configure --enable-tests --enable-profiling --flags=profiling --flags=tracing
$ cabal build
$ ./dist/build/hnix/hnix -v5 --trace <args> +RTS -xc

Note that this will run quite slowly, but will give the most information as to what might potentially be going wrong during parsing or evaluation.

Building with benchmarks enabled

To build hnix with benchmarks enabled:

$ nix-shell --arg doBenchmarks true
$ cabal configure --enable-tests --enable-benchmarks
$ cabal build
$ cabal bench

Building with profiling enabled

To build hnix with profiling enabled:

$ nix-shell
$ cabal configure --enable-tests --enable-profiling --flags=profiling
$ cabal build
$ ./dist/build/hnix/hnix <args> +RTS -p

Building with GHCJS

From the project root directory, run:

$ NIX_CONF_DIR=$PWD/ghcjs nix-build ghcjs

This will build an hnix library that can be linked to your GHCJS application.

Using the Cachix binary cache

If you're on macOS, you can use the binary cache at Cachix to avoid building the specific dependencies used by hnix. Just use these commands:

nix-env -iA cachix -f
cachix use hnix

How you can help

Issue Tracker Backlog

If you're looking for a way to help out, try taking a look here. When you find an issue that looks interesting to you, comment on the ticket to let others know you're working on it; look for others who might have done the same. You can talk with everyone live on Gitter.

When you're ready to submit a pull request, test it with:

git submodule update --init --recursive
nix-shell --run "LANGUAGE_TESTS=yes cabal test"

Make sure that all the tests that were passing prior to your PR are still passing afterwards; it's OK if no new tests are passing.

Evaluating Nixpkgs with HNix

Currently the main high-level goal is to be able to evaluate all of nixpkgs. To run this yourself, first build hnix with nix-build, then run the following command:

./result/bin/hnix --eval -E "import <nixpkgs> {}" --find
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