Läsp

A Lisp implementation in Ruby.

Features

• Very concise core library written in Ruby
• Standard library written in Läsp itself
• Interactive REPL with auto-closing of missing trailing parentheses
• Fully functional macro system
• Interoperability with Ruby

Installation

It needs Ruby to work, on Mac or most Linux OS:s it's already there and you can simply

gem install lasp

# If it doesn't work you might need to sudo
sudo gem install lasp

# You can update to the latest version the same way:
gem update lasp
sudo gem update lasp

Running

After installing you can invoke lasp for a REPL or provide a lasp-file to execute.

# An interactive prompt that lets you play with the language
lasp

# Run lasp-files
lasp path/to/program.lasp

The language

Please reference the documentation for specific definitions and examples of all available functions.

Examples

More advanced examples can be found in EXAMPLES.md, you can also look at the standard library which is implemented in Läsp itself.

(+ 1 2 3) ;; => 6

(def x 5)
x ;; => 6

(sum (list 5 10 15)) ;; => 30

(def inc (fn (x) (+ x 1)))
(inc 5) ;; => 6

Comments

Comments start with a ; and end at the end of a line

; This is a comment
(+ 1 2) ; This is also a comment

Developing

Run the specs

rake

Dev REPL

# This is basically just a shorthand for `rake install && lasp`
rake repl