Working on parsing single newlines

src/MdToHTML.hs

@@ -21,6 +21,7 @@ data MdToken
   | Header HeaderLevel MdToken
   | Para MdToken
   | Line [MdToken]
+  | SingleNewline -- A single newline is rendered as a space.
   | Linebreak
   | HorizontalRule
   | Blockquote MdToken
@@ -42,6 +43,7 @@ instance Show MdToken where
   show (Para token) = "<p>" ++ show token ++ "</p>"
   show (Line tokens) = concat (map show tokens)
   show Linebreak = "<br>"
+  show SingleNewline = " "
   show HorizontalRule = "---------"
   show (Blockquote token) = "BLOCK" ++ show token
   show (UnordList tokens) = "UNORD" ++ concat (map show tokens)
@@ -87,12 +89,11 @@ lineToList (Line tokens) = tokens
 parseHeader :: ReadP MdToken
 parseHeader = do
   skipSpaces
-  headers <- many1 mustBeHash
+  headers <- munch1 (== '#')
   when
     ((length headers) > 6)
     pfail
-  _ <- string " "
---  text <- manyTill (get) ((string "\n") <|> (eof >> return ""))-- Parse until EOL or EOF
+  skipSpaces
   text <- munch1 (/= '\n')
   Text.ParserCombinators.ReadP.optional (char '\n')
   let parsedText = fst $ leftmostLongestParse parseLine text
@@ -128,6 +129,11 @@ parseLinebreak = do
   char '\n'
   return Linebreak
 
+parseSingleNewline :: ReadP MdToken
+parseSingleNewline = do
+  char '\n'
+  return SingleNewline
+
 -- Parse a regular string as a Unit.
 parseString :: ReadP MdToken
 parseString = do
@@ -136,7 +142,7 @@ parseString = do
   return (Unit (firstChar : text))
 
 lineParsers :: [ReadP MdToken]
-lineParsers = [parseLinebreak, parseBold, parseItalic, parseString] -- A 'line' doesn't include a 'header'
+lineParsers = [parseLinebreak, parseSingleNewline, parseBold, parseItalic, parseString] -- A 'line' doesn't include a 'header'
 
 -- List of all parsers
 allParsers :: [ReadP MdToken]
@@ -154,7 +160,6 @@ parseLine = do
   remaining <- look
   when (null remaining) pfail
   parsed <- parseMany parseLineToken
-  --         traceM $ show parsed
   return (Line parsed)
 
 -- Parse a paragraph, which is a 'Line' (can span multiple actual lines), separated by double-newlines.