function changeLang(to_which_lang)
{
	to_which_lang = '/' + to_which_lang + '/';
	var uri = window.location.href;
	
	var filter_eng = /eng/;
	var filter_schi = /schi/;
	var filter_tchi = /tchi/;
	
	if (filter_eng.test(uri))
	{
		uri = uri.replace(/[\/]+eng[\/]+/g, to_which_lang);
	}
	
	if (filter_schi.test(uri))
	{
		uri = uri.replace(/[\/]+schi[\/]+/g, to_which_lang);
	}
	
	if (filter_tchi.test(uri))
	{
		uri = uri.replace(/[\/]+tchi[\/]+/g, to_which_lang);
	}
	
	window.location = uri;
}