mruby.zig

Build mruby using zig (no rake!).

About

Yeah, but your scientists were so preoccupied with whether or not they could, they didn't stop to think if they should.

--- Jeff Goldblum

This project builds MRuby from source, only using Zig.

This means we emulate MRuby's non-trivial Rake-based build process entirely in Zig.

Issues

• Non-standard library gems that use any Ruby logic in their mrbgem.rake files aren't supported
• Symbol preallocation isn't supported (this depends on Ruby regex to create the C files)
• Using mruby.zig in transitive Zig dependencies will likely cause issues (just use it globally in one package for now)
• We have to fork MRuby just to add back mrbgems/mruby-compiler/core/y.tab.c

Usage

Command line tools

To install all the CLI programs:

zig build

$ tree zig-out/bin/
zig-out/bin/
├── host-mrbc
├── mirb
├── mrbc
├── mrbtest
├── mruby
└── mruby-strip

See zig build -h for information about everything that's available:

zig build -h

Usage: /path/to/zig build [steps] [options]

Steps:
  install (default)            Copy build artifacts to prefix path
  uninstall                    Remove build artifacts from prefix path
  mrbc                         Run mrbc
  host-mrbc                    Run host-mrbc
  mruby                        Run mruby
  mirb                         Run mirb
  mrdb                         Run mrdb
  mruby-strip                  Run mruby-strip
  mrbtest                      Run mrbtest
  example-c                    Run src/example.c
  example-rb                   Run src/example.rb
  example-zig                  Run src/example.zig

To run MRuby's tests:

zig build mrbtest

mrbtest - Embeddable Ruby Test

...............................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................
  Total: 1647
     OK: 1647
     KO: 0
  Crash: 0
Warning: 0
   Skip: 0
   Time: 1.07 seconds

To use mirb, mruby, etc:

$ zig build mirb
mirb - Embeddable Interactive Ruby Shell

> MRUBY_VERSION
 => "3.3.0"

Examples

To run the examples:

zig build example-c
zig build example-rb
zig build example-zig

Cross compilation

Linux/Mac are the only targets currently supported, but support for others shouldn't be difficult.

zig build -Doptimize=ReleaseFast -Dtarget=x86_64-macos-none
zig build -Doptimize=ReleaseFast -Dtarget=x86_64-linux-musl
zig build -Doptimize=ReleaseFast -Dtarget=x86_64-linux-gnu

Using in a Zig project

Add to your build.zig.zon:

zig fetch --save=mruby "git+https://github.com/jethrodaniel/mruby.zig#main"

Then update your build.zig like so:

TODO

For more detail, see the example-zig step in build.zig, and the example file, src/example.zig.

TODO: document creating and using custom gems, using only a subset of the standard library, etc

Contributing

Bug reports and pull requests are welcome at https://github.com/jethrodaniel/mruby.zig

Acknowledgements

This project was inspired by https://github.com/dantecatalfamo/mruby-zig (MIT):

Some differences:

• we use @cImport instead of zig bindings
• we use zig build instead of rake

License

MIT, same as MRuby.