var parseExpression = function(str) {
	var openBracket, closeBracket, variants, head, tail;
	var result = [];
	closeBracket = str.indexOf('}');
	if (closeBracket === -1)
		return str;
	openBracket = str.substr(0, closeBracket).lastIndexOf('{');
	if (openBracket === -1)
		return str;
	variants = str.substr(openBracket+1, closeBracket - openBracket - 1).split('|');
	head = str.substr(0, openBracket)
	tail = str.substr(closeBracket + 1);
	for(var i=0; i < variants.length; i++) {
		result.push(parseExpression(head + variants[i] + tail));
	}
	return [].concat.apply([], result).filter(function(elem, pos, self){return self.indexOf(elem) == pos});
}