Methic 
Simple arithmetic implemented via Treetop.
Heavily based on treetop arithmetic example.
Installation
Add this line to your application's Gemfile:
gem 'methic'And then execute:
$ bundle
Or install it yourself as:
$ gem install methic
Usage
parser = MethicParser.new
parser.parse('0').eval #=> 0
parser.parse('1').eval #=> 1
parser.parse('123').eval #=> 123
parser.parse('x').eval('x' => 0) #=> 0
parser.parse('x').eval('x' => 3) #=> 3
parser.parse('y').eval('y' => 10) #=> 10
parser.parse('x + 5').eval('x' => 5) #=> 10
parser.parse('x - 5').eval('x' => 5) #=> 0
parser.parse('x * 2').eval('x' => 3) #=> 6
parser.parse('x / 2').eval('x' => 6) #=> 3
parser.parse('1 + 2 * 3 + 4').eval #=> 11
parser.parse('5 - 2 - 1').eval #=> 2
parser.parse('(5 + x) * (10 - y)').eval('x' => 0, 'y' => 5) #=> 25
parser.parse('4 == 4').eval #=> true
parser.parse('4 == 3').eval #=> falseContributing
- Fork it ( https://github.com/zizkovrb/methic/fork )
- Create your feature branch (
git checkout -b my-new-feature) - Commit your changes (
git commit -am 'Add some feature') - Push to the branch (
git push origin my-new-feature) - Create a new Pull Request