Luna Programming Language

Visual and textual functional programming language with a focus on productivity, collaboration and development ergonomics.

Luna is a developer’s whiteboard on steroids. Design, prototype, develop and refactor any application simply by connecting visual elements together. Collaborate with co-workers, interactively fine tune parameters, inspect the results and visually profile the performance in real-time.

Visit The Luna Website to learn more!

This repository contains the Luna compiler core and its command line version. For the full (visual) Luna Studio, please take a look at the Luna Studio repository. For installation and management tools, there is Luna Manager.

Getting Started

This will get you up and running for Luna development, with only a minimal amount of setup required.

Luna's build system is nice and simple, allowing you to bootstrap the compiler as long as you have an installation of The Haskell Stack and the Haskell parser generator happy.

You can install the latter just by running stack install happy, which should build the tool for your system and put it in your stack binary folder.

System Requirements

Luna runs on all reasonably new Linuxes, MacOS, and Windows. Luna was mostly tested on Ubuntu >= 14.04, Fedora >= 23, MacOS >= 10.11 (El Capitan) and Windows 10, although it should run fine on all Linux distros like Mint, Debian or Arch. Please report any issues here on GitHub or shoot an email to contact@luna-lang.org.

Getting the Sources

Given you've probably been reading this document on GitHub, you might have an inkling where to look!. You can clone Luna using two methods:

• Via HTTPS: We recommend you only use HTTPS if checking out the sources as read-only.

git clone https://github.com/luna/luna.git

• Via SSH: For those who plan on regularly making direct commits, cloning over SSH may provide a better user experience (but requires setting up your SSH Keys with GitHub).

git clone git@github.com:luna/luna.git

Building Luna

To build the command-line compiler interface along with all its sub-components, you will need to build the shell project. The instructions below assume that your luna repo is already cloned and we will refer to its location as $LUNA_REPO_PATH.

cd $LUNA_REPO_PATH
stack install

Note that the executable for the compiler will be located in $LUNA_REPO_PATH/dist/bin/public/luna folder. You may wish to add it to your $PATH.

Additionally, if you intend to simply use the Luna compiler (as opposed to tinkering with it, which requires frequent rebuilds), you may consider adding --ghc-options="-O2 -j4" to the stack install command. This should make the Luna compiler run considerably faster, at the cost of longer build times for building it.

Building Luna Components

It is also possible to build and test each component of Luna (e.g. core, parser) separately. To do this, pick the component you want from the following list, and then execute the following command:

stack build <component>
stack test <component>

Where <component> is one of the following:

• luna-core (found in $LUNA_REPO_PATH/core)
• lune-passes (found in $LUNA_REPO_PATH/passes)
• luna-package (found in $LUNA_REPO_PATH/package)
• luna-runtime (found in $LUNA_REPO_PATH/runtime)
• luna-shell (found in $LUNA_REPO_PATH/shell)
• luna-stdlib (found in $LUNA_REPO_PATH/stdlib)
• luna-syntax-text-lexer (found in $LUNA_REPO_PATH/syntax/text/lexer)
• luna-syntax-text-parser (found in $LUNA_REPO_PATH/syntax/text/parser)

Developing Luna's Libraries

Currently, all of the libraries owned by us that Luna depends on are in-tree, and can be found in the 'libs' folder. This is motivated by how often were were changing them purely to support Luna's development, and then having to go through the hackage release song and dance.

Instead, while these libraries are so actively developed. we've decided that they should live in Luna's tree, where they can be depended on by Luna and Luna Studio directly.

Working with these libraries is a breeze. If you want to make some changes, it's as simple as making them, and rebuilding to test them.

Building Luna for Release

In order to keep compile times down for development, we compile Luna with -fomit-interface-pragmas. However, this disables cross-module inlining, which is an important optimisation for Luna's performance.

In order to build Luna for maximum performance, you need to override this flag when giving the build command. This can be done as follows:

stack build --ghc-options="-fno-omit-interface-pragmas" <...>

It is recommended to always use this when building the benchmarks. You can use this additional argument with any of the commands listed above for development of individual components.

Running Luna

First, you need to create the project. This is as simple as executing luna init <project-path>, which will create a project in the directory specified with the correct structure. It will create a defaulted Main.luna file for you as well, allowing you to immediately execute this.

To interpret and run the project, simply type luna run in the main project directory. Alternatively, you can pass the project directory explicitly as follows:

luna run --target path/to/MyProject

Executing Luna on Standalone Files

The Luna interpreter is also capable of executing standalone Luna files. This can be done by passing a luna source file to the --target flag, similarly to the above.

Overriding the Standard Library Location

By default, a development build of Luna will look for the standard library in $LUNA_REPO_PATH/stdlib/, but it is possible to override this. If you would like to do so, you need to define the LUNA_STDLIB_OVERRIDE environment variable and set its value to the absolute path to the Luna standard library that you want to use.

As long as the variable is set, the compiler will use the location you provide, so don't forget to unset it if you would like to go back to using the included copy.

This environment variable override will also work for distributed binaries of Luna, and so provides a useful way to work on the standard library without needing to download and build Luna in its entirety.

Contributing to Luna

If you are interested in contributing to the development of Luna, please read the CONTRIBUTING.md file.

License

This repository is licensed under the Apache 2.0, as specified in the LICENSE file.

Please be aware that, as the commercial backing for Luna, New Byte Order Sp. z o. o. reserves the right under the CLA to use contributions made to this repository as part of commercially available Luna products.

If these terms are unacceptable to you, please do not contribute to the repository.

The Contributor License Agreement

As part of your first contribution to this repository, you need to accept the Contributor License Agreement. You will automatically be asked to sign the CLA when you make your first pull request.

Any work intentionally submitted for inclusion in Luna shall be licensed under this CLA.

The CLA you sign applies to all repositories associated with the Luna project (Luna, Luna Studio, etc), so you will only have to sign it once at the start of your contributions.