ライン文字列をパースし、その結果ごとに何かをさせる

Command.js

function Command () { this.map = []; }
(function (cp) {
    cp.set = function (pattern, cb) {
        if (typeof cb !== 'function')
            throw new Error('2nd argument must be "function"');
        if (typeof pattern !== 'string' && ! pattern instanceof RegExp)
            throw new Error('1st argument must be "string" of "regexp"');
        this.map.push([ pattern, cb ]);
        return this;
    };
    cp.parse = function (input) {
        var i   = 0
          , len = this.map.length
          , item
        ;
        for (var i = 0, len = this.map.length; i < len; i++) {
            item = this.map[i];
            if (typeof item[0] === 'string' && item[0] === input)
                return [ item[1], [ input ] ];
            if (item[0] instanceof RegExp && item[0].test(input))
                return [ item[1], input.match(item[0]) ];
        }
    };
})(Command.prototype);

example.js

var cmd = new Command;
cmd.set(':list', function (args) {
    storage.list();
})
.set(/^:(mak|nam|gnr|com|mch|act)\s+(.+?)$/, function (args) {
    storage.find({ category : args[1]
                 , value    : args[2]
                });
})
.set(/^[^:].*?$/, function (args) {
    storage.find({ category : 'mak'
                 , value    : args[0]
                });
})
;

$('#form1').onsubmit(function () {
    var res = cmd.parse($("#query").value);
    if (! res) return $('statusline').innerHTML =
                           escapeHTML('#quey.value is not "command"');
    res[0](res[1]);
});