@@ -46,7 +46,7 @@ module Text.Pandoc.Writers.HTML (
4646import Control.Monad.State
4747import Data.Char (ord, toLower)
4848import Data.List (intersperse, isPrefixOf)
49−import Data.Maybe (catMaybes, fromMaybe, isJust)
49+import Data.Maybe (catMaybes, fromMaybe, isJust, isNothing)
5050import Data.Monoid ((<>))
5151import Data.String (fromString)
5252import Network.HTTP (urlEncode)
@@ -192,6 +192,9 @@ writeHtmlString' st opts d = do
192192 case writerTemplate opts of
193193 Nothing -> return $ renderHtml body
194194 Just tpl -> do
195+ -- warn if empty lang
196+ when (isNothing (getField "lang" context :: Maybe String)) $
197+ report NoLangSpecified
195198 -- check for empty pagetitle
196199 context' <-
197200 case getField "pagetitle" context of