Hylo is a programming language that leverages mutable value semantics and generic programming for high-level systems programming.
This repository contains the sources of the reference implementation of Hylo. Please visit our website to get more information about the language itself.
This project is written in Swift and distributed in the form of a package, built with Swift Package Manager. You will need Swift 5.9 or higher to build the compiler from sources. The repository contains submodules, so when you clone it, be sure you've got them.
Windows users:
- Although this project is not Unix-specific, Windows support is not guaranteed due to the instability of continuous integration (see issue 252 and Swifty-LLVM/issue 24).
- This repository contains symbolic links, so you'll need to enable support for them before checking it out.
You can skip directly to step 3 if you're doing development exclusively in a devcontainer. Otherwise:
-
Install LLVM 15 or later on your system (e.g.
brew install llvm) -
Have the above installation's
llvm-configin yourPATH. Homebrew, for example, doesn't do that automatically; you'd need something like:export PATH="$(brew --prefix --installed llvm)/bin:$PATH"
-
In this project's root directory.
swift package resolveto get themake-pkgconfigtool..build/checkouts/Swifty-LLVM/Tools/make-pkgconfig.sh llvm.pcto generate LLVM's library description- Either
sudo mkdir -p /usr/local/lib/pkgconfig && sudo mv llvm.pc /usr/local/lib/pkgconfig/(if you want to use Xcode)- or,
export PKG_CONFIG_PATH=$PWDin any shell where you want to work on this project
You may compile Hylo's compiler with the following commands:
swift build -c releaseThat command will create an executable named hc in .build/release.
That's Hylo's compiler!
To test your compiler,
swift test -c release --parallelWhile Hylo supports Linux natively, it also provides a Devcontainer specification to develop for Linux on other platforms through a Docker container. Our Linux CI uses this specification; this makes it possible to run Linux CI locally on other operating systems like macOS. While this specification should work for any IDE that supports devcontainers, keep in mind this team only uses VSCode.
When opening the Hylo project in VSCode for the first time, you should be prompted to install the extension recommendations in .vscode/extensions.json. If you are not prompted, manually install the extensions by searching for the extension identifiers in the Extensions Marketplace.
Then, build the Devcontainer with the VSCode command: > Dev Containers: Rebuild and Reopen in Container.
Finally, open a new integrated terminal in VSCode and confirm that the shell user is vscode. You can run whoami to check this.
That integrated terminal is connected to the Devcontainer, as if by ssh.
Use the make-pkgconfig tool to configure LLVM's library description (see steps 3 in prerequisites).
You can now run swift test -c release to build and test for Linux.
The Hylo repository files are mounted into the container, so any changes made locally (in VSCode or in other editors) will be automatically propagated into the Devcontainer. However, if you need to modify any of the files in the .devcontainer directory, you will need to rebuild the container with > Dev Containers: Rebuild and Reopen in Container.
This project is under active development; expect things to break and APIs to change.
The compiler pipeline is organized as below. You can select how deep the compiler should go through the pipeline with the following options:
--emit raw-ast: Only parse the input files and output an untyped AST as a JSON file.--typecheck: Run the type checker on the input.--emit raw-ir: Lower the typed AST into Hylo IR and output the result in a file.--emit ir: Run mandatory IR passes and output the result in a file.--emit llvm: Transpile the program to LLVM and output LLVM IR.--emit intel-asm: Output Intel assembly for all user module(s).--emit binary(default): Produce an executable.
For example, hc --emit raw-ast -o main.json main.hylo will parse main.hylo, write the untyped AST in main.json, and exit the pipeline.
A more detailed description of the current implementation status is available on our roadmap page.
| Conference | Year | Speaker | Title |
|---|---|---|---|
| C++Now | 2022-05 | Dave Abrahams | Keynote: A Future of Value Semantics and Generic Programming Part 1 |
| C++Now | 2022-05 | Dave Abrahams & Dimi Racordon | Keynote: A Future of Value Semantics and Generic Programming Part 2 |
| CppNorth | 2022-07 | Dave Abrahams | Lightning Talk: An Object Model for Safety and Efficiency by Definition |
| CppCon | 2022-09 | Dave Abrahams | Value Semantics: Safety, Independence, Projection, & Future of Programming |
| CppCon | 2022-09 | Dimi Racordon | Val: A Safe Language to Interoperate with C++ |
| ACCU | 2023-03 | Lucian Radu Teodorescu | Concurrency Approaches: Past, Present, and Future |
| Podcast | Episode | Date | Guest | Title |
|---|---|---|---|---|
| CppCast | 352 | 2023-01-20 | Dimi Racordon | Val and Mutable Value Semantics |
| ADSP | 137 | 2023-07-07 | Sean Parent | Sean Parent on Hylo (vs Rust)! |
| ADSP | 138 | 2023-07-14 | Sean Parent | Sean Parent on Hylo! (Part 2) |
We welcome contributions to Hylo. Please read through CONTRIBUTING.md for details on how to get started.
You can also get in touch with the community by joining our Slack or one of our Zoom Meetings (ID: 633 2146 3694, Passcode: 409180) on Tuesdays and Thursdays, 12:30-1:00 Pacific time.
Hylo is distributed under the terms of the Apache-2.0 license. See LICENSE for details.