Factored out registerHeader from markdown reader, added to Parsing.

Text.Pandoc.Parsing now exports registerHeader, which can be
used in other readers.

src/Text/Pandoc/Parsing.hs

@@ -75,6 +75,7 @@ module Text.Pandoc.Parsing ( (>>~),
                              SubstTable,
                              Key (..),
                              toKey,
+                             registerHeader,
                              smartPunctuation,
                              withQuoteContext,
                              singleQuoteStart,
@@ -151,6 +152,7 @@ where
 import Text.Pandoc.Definition
 import Text.Pandoc.Options
 import Text.Pandoc.Builder (Blocks, Inlines, rawBlock, HasMeta(..))
+import qualified Text.Pandoc.Builder as B
 import Text.Pandoc.XML (fromEntities)
 import qualified Text.Pandoc.UTF8 as UTF8 (putStrLn)
 import Text.Parsec
@@ -162,11 +164,13 @@ import Text.Pandoc.Shared
 import qualified Data.Map as M
 import Text.TeXMath.Macros (applyMacros, Macro, parseMacroDefinitions)
 import Text.Pandoc.Compat.TagSoupEntity ( lookupEntity )
+import Text.Pandoc.Asciify (toAsciiChar)
 import Data.Default
 import qualified Data.Set as Set
 import Control.Monad.Reader
 import Control.Applicative ((*>), (<*), (<$), liftA2)
 import Data.Monoid
+import Data.Maybe (catMaybes)
 
 type Parser t s = Parsec t s
 
@@ -886,6 +890,34 @@ type KeyTable = M.Map Key Target
 
 type SubstTable = M.Map Key Inlines
 
+--  | Add header to the list of headers in state, together
+--  with its associated identifier.  If the identifier is null
+--  and the auto_identifers extension is set, generate a new
+--  unique identifier, and update the list of identifiers
+--  in state.
+registerHeader :: Attr -> Inlines -> Parser s ParserState Attr
+registerHeader (ident,classes,kvs) header' = do
+  ids <- stateIdentifiers `fmap` getState
+  exts <- getOption readerExtensions
+  let insert' = M.insertWith (\_new old -> old)
+  if null ident && Ext_auto_identifiers `Set.member` exts
+     then do
+       let id' = uniqueIdent (B.toList header') ids
+       let id'' = if Ext_ascii_identifiers `Set.member` exts
+                     then catMaybes $ map toAsciiChar id'
+                     else id'
+       updateState $ \st -> st{
+              stateIdentifiers = if id' == id''
+                                    then id' : ids
+                                    else id' : id'' : ids,
+              stateHeaders = insert' header' id' $ stateHeaders st }
+       return (id'',classes,kvs)
+     else do
+        unless (null ident) $
+          updateState $ \st -> st{
+               stateHeaders = insert' header' ident $ stateHeaders st }
+        return (ident,classes,kvs)
+
 -- | Fail unless we're in "smart typography" mode.
 failUnlessSmart :: Parser [tok] ParserState ()
 failUnlessSmart = getOption readerSmart >>= guard

src/Text/Pandoc/Readers/Markdown.hs

@@ -49,7 +49,6 @@ import Text.Pandoc.Builder (Inlines, Blocks, trimInlines, (<>))
 import Text.Pandoc.Options
 import Text.Pandoc.Shared
 import Text.Pandoc.XML (fromEntities)
-import Text.Pandoc.Asciify (toAsciiChar)
 import Text.Pandoc.Parsing hiding (tableWith)
 import Text.Pandoc.Readers.LaTeX ( rawLaTeXInline, rawLaTeXBlock )
 import Text.Pandoc.Readers.HTML ( htmlTag, htmlInBalanced, isInlineTag, isBlockTag,
@@ -471,31 +470,6 @@ block = choice [ mempty <$ blanklines
 header :: MarkdownParser (F Blocks)
 header = setextHeader <|> atxHeader <?> "header"
 
---  returns unique identifier
-addToHeaderList :: Attr -> F Inlines -> MarkdownParser Attr
-addToHeaderList (ident,classes,kvs) text = do
-  let header' = runF text defaultParserState
-  exts <- getOption readerExtensions
-  let insert' = M.insertWith (\_new old -> old)
-  if null ident && Ext_auto_identifiers `Set.member` exts
-     then do
-       ids <- stateIdentifiers `fmap` getState
-       let id' = uniqueIdent (B.toList header') ids
-       let id'' = if Ext_ascii_identifiers `Set.member` exts
-                     then catMaybes $ map toAsciiChar id'
-                     else id'
-       updateState $ \st -> st{
-              stateIdentifiers = if id' == id''
-                                    then id' : ids
-                                    else id' : id'' : ids,
-              stateHeaders = insert' header' id' $ stateHeaders st }
-       return (id'',classes,kvs)
-     else do
-        unless (null ident) $
-          updateState $ \st -> st{
-               stateHeaders = insert' header' ident $ stateHeaders st }
-        return (ident,classes,kvs)
-
 atxHeader :: MarkdownParser (F Blocks)
 atxHeader = try $ do
   level <- many1 (char '#') >>= return . length
@@ -504,7 +478,7 @@ atxHeader = try $ do
   skipSpaces
   text <- trimInlinesF . mconcat <$> many (notFollowedBy atxClosing >> inline)
   attr <- atxClosing
-  attr' <- addToHeaderList attr text
+  attr' <- registerHeader attr (runF text defaultParserState)
   return $ B.headerWith attr' level <$> text
 
 atxClosing :: MarkdownParser Attr
@@ -543,7 +517,7 @@ setextHeader = try $ do
   many (char underlineChar)
   blanklines
   let level = (fromMaybe 0 $ findIndex (== underlineChar) setextHChars) + 1
-  attr' <- addToHeaderList attr text
+  attr' <- registerHeader attr (runF text defaultParserState)
   return $ B.headerWith attr' level <$> text
 
 --