RubyLisp (rbl)

A Lisp dialect of Ruby.

Why?

Lisps are great, but I haven't found one usable enough (by my own standards) for scripting. Clojure is my favorite language from a design perpective, and the fact that you can leverage existing JVM libraries is super convenient. But there's just one problem -- its startup time is so slow.

Common Lisp is nice; it's a powerful Lisp, and it's fast. But it's not always easy to find X existing library to do Y thing, it's maybe a little too low-level for my liking, and the tooling situation is not so great.

Ruby is great for scripting, cross-platform, and has hella good libraries, but there's just one problem -- it's not a Lisp.

I've played around with the make-a-lisp guide a few times in the past to build Lisps for fun in languages like Rust. I thought it would be interesting to try and build for myself the convenient scripting Lisp that I always wanted. It turns out that it's super easy to write a Lisp interpreter, but it's awful time-consuming to build a whole language from scratch. I had a shower thought that the Ruby standard library can already do about 80% of the things a faithful Lisp should do, so maybe the path of least resistance to building the Lisp of my dreams is to write the interpreter in Ruby and totally cheat on all of the function implementations by delegating to functions and types that have already been implemented in the Ruby stdlib.

I think I was right. Check it out, everyone -- you can write your Ruby scripts in Lisp now!

Features

NOTE: RubyLisp is still in early development. If you find something is broken or missing, please file an issue, or better yet, fork this repo, add/fix it yourself, and make a Pull Request!

Syntax and stdlib functions heavily influenced by Clojure.
Easy, convenient Ruby inter-op.
Fire up a REPL or run it in a script.
Immutable linked lists, vectors, and hashes courtesy of the Hamster library.
(TODO) Macros, Clojure-style.
(TODO) Namespaces, Clojure-style.
(TODO) Dependency management / the ability to use some sort of build tool to include Ruby libraries and use them via inter-op.

Examples

TODO

Installation

Run this:

$ gem install rbl

Usage

To start a REPL:

$ rbl

To interpret a file containing RubyLisp code:

$ rbl my_sweet_rubylisp_script.rbl

Or, if you'd like, you can include a shebang, make the script executable and run it directly:

$ cat << EOF > reticulate_splines.rbl
#!/usr/bin/env rbl
(print "Reticulating splines... ")
(Kernel::sleep 2)
(println "done.")
EOF

$ chmod +x reticulate_splines.rbl

$ ./reticulate_splines.rbl
Reticulating splines... done.

Development

After checking out the repo, run bin/setup to install dependencies. Then, run rake spec to run the tests. You can also run bin/console for an interactive prompt that will allow you to experiment.

To install this gem onto your local machine, run bundle exec rake install. To release a new version, update the version number in version.rb, and then run bundle exec rake release, which will create a git tag for the version, push git commits and tags, and push the .gem file to rubygems.org.

Contributing

Contributions welcome!

As a general rule, I want RubyLisp to mirror the behavior of Clojure as closely as possible. If you have a favorite Clojure function/macro and it isn't included in RubyLisp yet, why not add it yourself and make a Pull Request? :)

License

The gem is available as open source under the terms of the MIT License.