+toHtml :: [Markup] -> String
+toHtml [] = []
+toHtml ((Paragraph):xs) = "<p>\n"++toHtml xs
+toHtml ((Text s):xs) = s++toHtml xs
+toHtml ((Link l d):xs) = "<link: "++l++" desc: "++d++">"++toHtml xs
+toHtml ((Bold d):xs) = "<b>"++toHtml d++"</b>"++toHtml xs
+toHtml ((Emph d):xs) = "<em>"++toHtml d++"</em>"++toHtml xs
+toHtml ((Underline d):xs) = "<u>"++toHtml d++"</u>"++toHtml xs
+toHtml ((Strike d):xs) = "<strike>"++toHtml d++"</strike>"++toHtml xs
+toHtml ((Heading n d):xs) = "\n<h"++show n++">"++toHtml d++"</h"++show n++">\n"++toHtml xs
+toHtml ((Url l):xs) = "<link: "++l++">"++toHtml xs
+toHtml ((Pre s):xs) = "<pre>"++s++"</pre>"++toHtml xs
+toHtml ((List l):xs) = "<ul>\n"++(unlines $ map (\s -> "<li>"++toHtml s++"</li>\n") l) ++ "</ul>"++toHtml xs
+
+htmlOutput s = case parse wikiParser "" s of
+ Right n -> putStr (toHtml n)
+ Left e -> print e