/*
 RegExp.prototype
*/

RegExp.prototype.isRegExp = true;

RE = Regexp = RegExp;
RegExp.escape = function(str){
	return str.replace(/(\\|\[|\]|\(|\)|\{|\}|\^|\-|\$|\||\+|\*|\?|\.|\!)/g,"\\$1");
};

// よく使われる正規表現を高速化
RE.func_body = /\{((:?.|\n)*)\}/;
RE.func_name = /function ([\w$]+)/;
RE.func_args = /\(([^)]*)/;

function MatchData(){
	var self = this;
	this.leftContext = this.pre_match  = new LazyString(function(){
		return self.input.slice(0,self.index)
	});
	this.rightContext = this.post_match = new LazyString(function(){
		return self.input.slice(self.index+self.$0.length)
	});
	return this;
}
MatchData.prototype.update = function(a){
	this.lastMatch = this.$0 = a[0];
	this.match = this.captures = [];
	for(var i=1;i<a.length-2;i++){
		this.match.push(a[i]);
		this["$"+i] = a[i];
	}
	this.index = a[a.length-2];
	this.input = this.$_ = a[a.length-1];
}

// 関数をreplaceのcallbackとして使いやすいように
Function.prototype.replace_callback = function(thisObject){
	var self = this;
	var match = new MatchData();
	var newfunc = self.rebuildWith(match);
	return function(){
		match.update(arguments);
		return newfunc.call(thisObject)
	}
}