Uso de la función call

main.js

jQuery(function(){
    jQuery('input[type=submit]').click(function(evt){
        evt.preventDefault();
        
        var string = jQuery('input[type=text]').val();
        var simpleParser = {},
            advancedParser = {},
            wonderfulParser = {};
        
        PARSER.call(simpleParser);
        PARSER.call(advancedParser, {g: function(argv){}});
        PARSER.call(wonderfulParser, jQuery.extend(true, {}, advancedParser.rules, {v: function(argv){}}));
        
        simpleParser.parser(string);
        advancedParser.parser(string);
        wonderfulParser.parser(string);
    });
});

parser.js

var PARSER = function(newRules){
    var _self = this;
    var defaultRules = {
            l: function(argv){},
            p: function(argv){},
            d: function(argv){}
    };
    var rules = jQuery.extend(true, {}, defaultRules, newRules);
    var REGEX = /(\w\s{1}[\d|\w|/|,]*)/;
    this.parser = function(string){
        if(REGEX.test(string)) {
          var matches = string.match(REGEX);
          for(var match in matches) {
              _self.execute(matches[match]);
          }
        } else {
            throw 'No found string to parser';
        }
    };

    this.execute = function(command){
        console.info(typeof command);
        var command = command.split(' ');
        if(typeof rules[command[0]] === 'function'){
            rules[command[0]].call(command[1]||[]);
        }else{
            throw 'No rules defined for ' + command[0] + ' whith argv ' + command[1];
        }
    }
};