Rbsiev

SICP evaluator in Ruby.

Or, Ruby で書いた SICP の evaluator.

It is intended to be a part of Scheme implementation written in Ruby.

Installation

Execute:

$ gem install rbsiev

Usage

Run the simple REPL as:

$ rbsiev

Then, you can input Scheme program.

Supported Syntax

In 0.1.0, the evaluator mostly corresponds to the one in SICP 4.1.1 - 4.1.6.

See the wiki page for more information about the progress of implementing.

Literals

• boolean value (#f and #t),
• an empty list (()),
• a string enclosing with double-quotations, such "hoge"
• numbers (integer, real, rational, and complex)

Primitive procedures

• arithmetic operators (+, -, *, /, %),
• comparison operators (=, <, >, <=, >=)
• cons, car, cdr
• null?, pair?, list?, number?
• list, append
• write, display

Syntax to be evaluated

• lambda expression
  • such (lambda (n) (+ n 1))
• procedure application
  • such (foo 1)
• conditional expression
  • if, cond, when, unless
• logical test
  • and, or
• assignment
  • set!
• definition
  • define
• sequence
  • begin
• local bindings
  • let, let*, letrec, letrec*
• loop
  • do

Related projects

• Lexical Analyzer for Scheme - mnbi/rbscmlex
• Abstract Syntax Tree and Syntax Analyzer for Scheme - mnbi/rubasteme
• Ruby wit Syntax Sugar of Scheme - mnbi/rus3
• A small Scheme implementation in Ruby - mnbi/rubeme

Development

After checking out the repo, run bin/setup to install dependencies. Then, run rake test 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

Bug reports and pull requests are welcome on GitHub at https://github.com/mnbi/rbsiev.

License

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