Plush

Plush is an experimental toy programming language and virtual machine for fun and teaching purposes. It follows a minimalistic design philosphy and draws inspiration from JavaScript, Lox, Lua, Python and Rust. Plush supports actor-based parallelism and is designed such that there is no global VM lock. The language has straightforward semantics and is built around a simple stack-based interpreter. The codebase is well-commented, has very few depencencies, and good cross-platform support. Please do note however that this project is very much a fun side-project and a work in progress. You're likely to run into bugs and missing features.

If you think that Plush is cool, you can support my work via GitHub Sponsors ❤️

The Plush language supports:

• Dynamic typing
• Classes
• Closures/lambdas
• Dynamic arrays aka vectors/lists
• UTF-8 strings (work in progress)
• Dictionaries with JS-like syntax (work in progress)
• Memory safe, actor-based parallelism
• A native byte array type
• A simple frame buffer API for graphics and animations
• An extensible set of host functions defined in src/host.rs

Caveats and limitations:

• The language is still very much incomplete
  • You may run into bugs or missing features
• Lack of error messages or good error handling
  • You may have to look at the source code to figure things out
  • We could use your help in improving error messages
• Copying garbage collector planned but not yet implemented
  • Currently relying on alloc-until-you-crash technology (TM)
• Imports, support for multiple source files planned but not yet implemented

For a detailed guide to the Plush language, please see the Plush Language Quickstart.

Build Instructions

Dependencies:

• The Rust toolchain
• The SDL2 libraries

Installing Rust and SDL2 on macOS

Install the SDL2 package:

brew install sdl2

Add this to your ~/.zprofile:

export LIBRARY_PATH="$LIBRARY_PATH:$(brew --prefix)/lib"

Install the Rust toolchain:

curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh

Installing Rust and SDL2 on Debian/Ubuntu

Install the SDL2 package:

sudo apt-get install libsdl2-dev

Install the Rust toolchain:

curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh

Installing Rust and SDL2 on Windows

Follow the Windows-specific instructions to install the Rust toolchain.

Get SDL2.dll from one of SDL2 Releases.

Copy SDL2.dll (unzip) to the root of your cloned repo.

Compiling the Project

cargo build

To run the test suite:

cargo test

To run a plush script:

# See example programs under /examples, /benchmarks and /tests
cargo run examples/helloworld.psh
cargo run examples/plasma.psh

Open Source License

The code for Plush, its VM and associated tools is shared under the Apache-2.0 license. The example code in the /examples directory are shared under the Creative Commons CC0 license.

Contributing

There is a lot of work to be done to get this project going and contributions are welcome.

A good first step is to look at open issues and read the available documentation. Another easy way to contribute is to create new example programs showcasing cool things you can do with Plush, or to report any bugs and issues you encounter. If you do report bugs, please provide as much context as possible, and the smallest reproduction you can come up with.

You can also search the codebase for TODO or FIXME notes:

grep -IRi "todo" .

In general, smaller pull requests are easier to review and have a much higher chance of getting merged than large pull requests. If you would like to add a new, complex feature or refactor the design of Plush, I recommend opening an issue or starting a discussion about your proposed changes first.

Also please keep in mind that one of the core principles of Plush is to minimize dependencies to keep the VM easy to install and easy to port. Opening a PR that adds dependencies to multiple new packages and libraries is unlikely to get merged. If you believe you have a valid argument in favor of doing so, please open an issue to share your point of view.