From eb93b31a17773056fe56c388b4422c513c1c6a91 Mon Sep 17 00:00:00 2001 From: Brent Yorgey Date: Sat, 11 May 2024 15:23:18 -0500 Subject: [PATCH] more comments --- src/swarm-lang/Swarm/Language/Parse.hs | 14 +++++++++++--- 1 file changed, 11 insertions(+), 3 deletions(-) diff --git a/src/swarm-lang/Swarm/Language/Parse.hs b/src/swarm-lang/Swarm/Language/Parse.hs index 13850b157..7ff5682bc 100644 --- a/src/swarm-lang/Swarm/Language/Parse.hs +++ b/src/swarm-lang/Swarm/Language/Parse.hs @@ -84,8 +84,10 @@ data Antiquoting = AllowAntiquoting | DisallowAntiquoting data CommentState = CS { _freshLine :: Bool - -- ^ Are we currently on a (so far) blank line, i.e. have there - -- been no nontrivial tokens since the most recent newline? + -- ^ Are we currently on a (so far) blank line, i.e. have there been + -- no nontrivial tokens since the most recent newline? This field + -- is updated every time we parse a lexeme or symbol (set to + -- false), or a newline (set to true). , _comments :: Seq Comment -- ^ The actual sequence of comments, in the order they were encountered } @@ -130,6 +132,9 @@ reservedWords = -- Approach for preserving comments taken from https://www.reddit.com/r/haskell/comments/ni4gpm/comment/gz0ipmp/ +-- | If we see a comment starting now, is it the first non-whitespace +-- thing on the current line so far, or were there other +-- non-whitespace tokens previously? getCommentSituation :: Parser CommentSituation getCommentSituation = do fl <- use freshLine @@ -162,7 +167,7 @@ sc = -- end-of-line specially. skipMany . choice . map hidden $ [ hspace1 - , eol *> (freshLine .= True) + , eol *> (freshLine .= True) -- If we see a newline, reset freshLine to True. , lineComment "//" , blockComment "/*" "*/" ] @@ -171,6 +176,9 @@ sc = -- assumes no leading whitespace and consumes all trailing -- whitespace. Concretely, we achieve this by wrapping every token -- parser using 'lexeme'. +-- +-- Also sets freshLine to False every time we see a non-whitespace +-- token. lexeme :: Parser a -> Parser a lexeme p = (freshLine .= False) *> L.lexeme sc p