jerkenstein calc plugin

calc.js

var  basic = /[0-9\+\-\*\/\%\.\,\(\)\s]/
    ,math_properties = /E|LN2|LN10|LOG2E|LOG10E|PI|SQRT1_2|SQRT2/
    ,math_methods = /abs|acos|asin|atan|atan2|ceil|cos|exp|floor|log|max|min|pow|random|round|sin|sqrt|tan/
    ,pattern = new RegExp('^\\?calc (('+basic.source+'|Math\\.('+math_properties.source+'|(('+math_methods.source+')\\()))+)$')


this.plugin = {
   'name': 'calc'
  ,'pattern': pattern
  ,'description': 'Calculate basic arithmetic.'
  ,'example': '?calc 2+2.'
  ,'action': function(message) {
    try{
      message.say(message.user + ': ' + message.match_data[1]+ ' = ' + eval(message.match_data[1]).toString())
    }catch(e){
      message.say('err')
    }
  }
  ,'url': 'http://gist.github.com/575830'
}