Add parsing support for the rST default-role directive.

1 files changed, 31 insertions, 3 deletions

diff --git a/src/Text/Pandoc/Readers/RST.hs b/src/Text/Pandoc/Readers/RST.hs
index 30d9aae44..2fbf11cf7 100644
--- a/src/Text/Pandoc/Readers/RST.hs
+++ b/src/Text/Pandoc/Readers/RST.hs
@@ -129,6 +129,7 @@ block = choice [ codeBlock
                , imageBlock
                , customCodeBlock
                , mathBlock
+               , defaultRoleBlock
                , unknownDirective
                , header
                , hrule
@@ -533,6 +534,21 @@ bulletList = many1 (listItem bulletListStart) >>=
              return . BulletList . compactify
 
 --
+-- default-role block
+--
+
+defaultRoleBlock :: GenParser Char ParserState Block
+defaultRoleBlock = try $ do
+    string ".. default-role:: "
+    role <- manyTill anyChar newline >>= return . removeLeadingTrailingSpace
+    updateState $ \s -> s { stateRstDefaultRole =
+        if null role
+           then stateRstDefaultRole defaultParserState
+           else role
+        }
+    return Null
+
+--
 -- unknown directive (e.g. comment)
 --
 
@@ -805,13 +821,25 @@ strong :: GenParser Char ParserState Inline
 strong = enclosed (string "**") (try $ string "**") inline >>= 
          return . Strong . normalizeSpaces
 
-interpreted :: [Char] -> GenParser Char st [Char]
+-- Parses inline interpreted text which is required to have the given role.
+-- This decision is based on the role marker (if present),
+-- and the current default interpreted text role.
+interpreted :: [Char] -> GenParser Char ParserState [Char]
 interpreted role = try $ do
+  state <- getState
+  if role == stateRstDefaultRole state
+     then try markedInterpretedText <|> unmarkedInterpretedText
+     else     markedInterpretedText
+ where
+  markedInterpretedText = try (roleMarker >> unmarkedInterpretedText)
+                          <|> (unmarkedInterpretedText >>= (\txt -> roleMarker >> return txt))
+  roleMarker = string $ ":" ++ role ++ ":"
   -- Note, this doesn't precisely implement the complex rule in
   -- http://docutils.sourceforge.net/docs/ref/rst/restructuredtext.html#inline-markup-recognition-rules
   -- but it should be good enough for most purposes
-  result <- enclosed (string $ ":" ++ role ++ ":`") (char '`') anyChar
-  return result
+  unmarkedInterpretedText = do
+      result <- enclosed (char '`') (char '`') anyChar
+      return result
 
 superscript :: GenParser Char ParserState Inline
 superscript = interpreted "sup" >>= \x -> return (Superscript [Str x])