Markdown reader: example_lists should work without startnum.

Closes  #4908.

src/Text/Pandoc/Readers/Markdown.hs

@@ -970,7 +970,9 @@ orderedList = try $ do
                <|> return (style == Example)
   items <- fmap sequence $ many1 $ listItem fourSpaceRule
                  (orderedListStart (Just (style, delim)))
-  start' <- (start <$ guardEnabled Ext_startnum) <|> return 1
+  start' <- if style == Example
+               then return start
+               else (start <$ guardEnabled Ext_startnum) <|> return 1
   return $ B.orderedListWith (start', style, delim) <$> fmap compactify items
 
 bulletList :: PandocMonad m => MarkdownParser m (F Blocks)

test/command/4908.md

@@ -0,0 +1,16 @@
+```
+% pandoc -f markdown_mmd+fancy_lists+example_lists -t native -t plain
+(@) Example one
+(@) Example two
+
+some text
+
+(@) Example three
+^D
+(1) Example one
+(2) Example two
+
+some text
+
+(3) Example three
+```