Crisp

Crisp is an experimental language written in Ruby, using treetop.

Crisp has a Lisp syntax and immutable data structures.

The main purpose of the language is to deal with the issues and problems when creating your own programming language.

Language features

• binding values to a symbol with def
• calculations with +, -, * and /
• comparisons with >, < and =
• conditional statements with if
• loop statements with loop/recur
• console output with println
• function creation with fn
• switch/case conditions with cond
• local binding with let
• dynamic loading of crisp source files with load
• head and tail functions for array with head and tail
• calling native ruby with .

Example

    # crisp
    >> (println "Hello World")
    Hello World
    =>
    >> (def fib (
    ?>   fn [n]
    ?>     (if (< n 2)
    ?>       n
    ?>         (+ (fib (- n 1)) (fib (- n i))))))
    => #<Crisp::Function:0x1005c2500>
    >> (fib 10)
    => 55
    >> (def factorial
    ?>   (fn [n]
    ?>     (loop [cnt n acc 1]
    ?>       (if (= 0 cnt)
    ?>         acc
    ?>         (recur (- cnt 1) (* acc cnt))))))
    => #<Crisp::Function:0x1001ad9d8>
    >> (factorial 12)
    => 479001600

For more examples see the examples directory in the repository.

Installation

    gem install crisp

Usage

To start an interactive shell: crisp

To run a crisp programm crisp /path/to/file