sample for jison

calc.jison

/* description: Parses end executes mathematical expressions. */

/* lexical grammar */
%lex
%%

\s+                   /* skip whitespace */
[0-9]+("."[0-9]+)?\b  return 'NUMBER'
"*"                   return '*'
"/"                   return '/'
"-"                   return '-'
"+"                   return '+'
"^"                   return '^'
"!"                   return '!'
"%"                   return '%'
"("                   return '('
")"                   return ')'
"PI"                  return 'PI'
"E"                   return 'E'
<<EOF>>               return 'EOF'
.                     return 'INVALID'

/lex

/* operator associations and precedence */

%left '+' '-'
%left '*' '/'
%left '^'
%right '!'
%right '%'
%left UMINUS

%start expressions

%% /* language grammar */

expressions
    : e EOF
        { return $1; }
    ;

e
    : e '+' e
        {$$ = new (require("./calc_node")).Add($1, $3);}
    | e '-' e
        {$$ = new (require("./calc_node")).Sub($1, $3);}
    | e '*' e
        {$$ = new (require("./calc_node")).Mul($1, $3);}
    | e '/' e
        {$$ = new (require("./calc_node")).Div($1, $3);}
    | e '^' e
        {$$ = new (require("./calc_node")).Pow($1, $3);}
    | e '!'
        {$$ = new (require("./calc_node")).Factorial($1);}
    | e '%'
        {$$ = new (require("./calc_node")).Percentage($1);}
    | '-' e %prec UMINUS
        {$$ = new (require("./calc_node")).Minus($2);}
    | '(' e ')'
        {$$ = $2;}
    | NUMBER
        {$$ = Number($1);}
    | E
        {$$ = (require("./calc_node")).E;}
    | PI
        {$$ = (require("./calc_node")).PI;}
    ;

calc_main.coffee

#
# See http://d.hatena.ne.jp/itchyny/20110711/1310387128
#    Jison入門!!!
#
# $ node -f
# v0.8.4
#
# $ coffee -v
# CoffeeScript version 1.3.3
#
# $ jison calc.json # generate cakc.js
#
# $ cat testcalc
# 1 + 2
#
# $ coffee calc_main.coffee
# ==========  1 + 2
# <Add>
#     left: 1
# right: 2
#     ==========  1 * 2 + PI
# <Add>
#     left: <Mul>
#         left: 1
#     right: 2
# right: <Object>
#         value: 3.141592653589793
#

toString = (obj, indent = "") ->
  s = '<' + ((if obj then obj.constructor.name else '')) + '>'
  for key of obj
    if obj.hasOwnProperty(key)
      val = obj[key]
      s += "\n#{indent}#{key}: "
      if typeof val is 'object'
        s += toString(val, indent + '    ')
      else if typeof val is 'function'
        s += val.name
      else
        s += val or ''
  s += "\n#{indent}#{obj}"  if typeof obj is 'number'
  s

exec = (input) ->
  require('./calc').parse(input)

args = process.argv.slice(1)
input = require('fs').readFileSync(require('path').resolve(args[1]), 'utf8')
x = exec(input)
console.log "==========  #{input}"
console.log toString(x)

input = '1 * 2 + PI'
x = exec(input)
console.log "==========  #{input}"
console.log toString(x)

calc_node.js

function Add(x, y) { this.left = x; this.right = y; }
function Sub(x, y) { this.left = x; this.right = y; }
function Mul(x, y) { this.left = x; this.right = y; }
function Div(x, y) { this.left = x; this.right = y; }
function Pow(x, y) { this.left = x; this.right = y; }
function Factorial(x) { this.value = x; }
function Percentage(x) { this.value = x; }
function Minus(x) { this.value = x; }
E = { value : Math.E };
PI = { value : Math.PI };

module.exports.Add = Add;
module.exports.Sub = Sub;
module.exports.Mul = Mul;
module.exports.Div = Div;
module.exports.Pow = Pow;
module.exports.Factorial = Factorial;
module.exports.Percentage = Percentage;
module.exports.Minus = Minus;
module.exports.E = E;
module.exports.PI = PI;

calctest

1 + 2