regex - Javascript - modify regexp constructor or add tokens -

i need parse input against complex regexp's have common elements.

i make "my text 2014".match(/{date}/);

where date long regexp or set of tokens like

regexp.tokens.date = /{year}|{month}|{day}/ etc.

and uses tokens

regexp.tokens.year = /** native regexp matching year number **/ 

i want {tokens} (recursively) parsed native regexp before testing.

in other words - want add list of tokens , meaning , able make regexp using them.

i trying modify constructor of regexp dont make change.

rather hacking around existing stuff, should create own wrappers.

something like:

function myregex(src,flags) {     for( var k in myregex.tokens) if( myregex.tokens.hasownproperty(k)) {         src = src.replace(new regexp("\\{"+k+"\\}","g"),myregex.tokens[k]);     }     this.pattern = new regexp(src,flags); }; myregex.tokens = {     "year": "your regex string here",     // ... }; myregex.prototype.test = function(str) {     return this.pattern.test(str); }; // define more methods needed 

to use:

var regex = new myregex("{date}"); console.dir(regex.test("my text 2014"));