let-go

Greetings loafers! (λ-gophers haha, get it?)

This is supposed to be a bytecode compiler and VM for a language resembling Clojure as close as possible.

Now, I know about candid82/joker and I 💛 it. Though, it has some drawbacks and design choices that I'd like to avoid.

Here are some nebulous goals in no particular order:

• [x] Quality entertainment,
• [ ] Implement as much of Clojure as possible - including persistent data types and true concurrency,
• [ ] Provide comfy two-way interop for arbitrary functions and types,
• [ ] Serve primarily as an embedded extension language,
• [ ] AOT (let-go -> standalone binary) would be nice eventually,
• [ ] Strech goal: let-go bytecode -> Go translation.
• [ ] ~~Pure Go, zero dependencies.~~ We use a lightweight line editor for the REPL now - alimpfard/line

Here are the non goals:

• Stellar performance,
• Being a drop-in replacement for clojure/clojure at any point,
• Being a linter/formatter/tooling for Clojure in general.

Current status

Can compile and eval basic Clojure flavored lisp.

The most impressive snippet so far

(ns server
  'http)

(http/handle "/" (fn [res req]
                   (println (now) (:Method req) (:URL req))
                   (.WriteHeader res 200)
                   (.Write res "hello from let-go :^)")))

(http/serve ":7070" nil)

See tests and examples for more examples.

Prerequisites and installation

Building or running let-go from source requires Go 1.17. There are no binary releases yet.

Running

Sure, you can! Just keep in mind that we're not there yet and it will likely blow up in your face. Just remember to leave an issue when it does 😊

The best way to take let-go for a spin right now is to clone this repo and run the REPL like this:

go run . 

To run an expression:

go run . -e '(+ 1 1)'

To run a file:

go run . test/hello.lg

Use the -r flag to run the REPL after the interpreter has finished with files and -e:

go run . -r test/simple.lg                # will run simple.lg first, then open up a REPL
go run . -r -e '(* fun 2)' test/simple.lg # will run simple.lg first, then (* fun 2) and REPL 

Building the interpreter -lg

To build the standalone interpreter:

make

This will produce the lg executable.

Follow me on twitter for nightly updates! 🌙