ex2 ((Strike d):xs) = "<strike>"++ex2 d++"</strike>"++ex2 xs
ex2 ((Heading n d):xs) = "\n<h"++show n++">"++ex2 d++"</h"++show n++">\n"++ex2 xs
ex2 ((Url l):xs) = "<link: "++l++">"++ex2 xs
ex2 ((Strike d):xs) = "<strike>"++ex2 d++"</strike>"++ex2 xs
ex2 ((Heading n d):xs) = "\n<h"++show n++">"++ex2 d++"</h"++show n++">\n"++ex2 xs
ex2 ((Url l):xs) = "<link: "++l++">"++ex2 xs