Create simple method for indentation parsing.

1 files changed, 9 insertions, 0 deletions

diff --git a/haddock-library/src/Documentation/Haddock/Parser.hs b/haddock-library/src/Documentation/Haddock/Parser.hs
index 5c607a1a..6bb88035 100644
--- a/haddock-library/src/Documentation/Haddock/Parser.hs
+++ b/haddock-library/src/Documentation/Haddock/Parser.hs
@@ -382,6 +382,15 @@ takeNonEmptyLine :: Parser String
 takeNonEmptyLine = do
     (++ "\n") . decodeUtf8 <$> (takeWhile1 (/= '\n') >>= nonSpace) <* "\n"
 
+-- | Takes indentation of first non-empty line.
+--
+-- More precisely: skips all whitespace-only lines and returns indentation
+-- (horizontal space, might be empty) of that non-empty line.
+takeIndent :: Parser BS.ByteString
+takeIndent = do
+  indent <- takeHorizontalSpace
+  "\n" *> takeIndent <|> return indent
+
 -- | Blocks of text of the form:
 --
 -- >> foo