diff --git a/ChangeLog b/ChangeLog --- a/ChangeLog +++ b/ChangeLog @@ -1,3 +1,6 @@ +2022-11-08 v1.7.0.1 + * Add CI for GHC 9.6.2 + * Correctly deal with comments when using GHC flag -haddock 2022-11-08 v1.7 * Support GHC 9.6.1 2022-11-08 v1.6.1 diff --git a/ghc-exactprint.cabal b/ghc-exactprint.cabal --- a/ghc-exactprint.cabal +++ b/ghc-exactprint.cabal @@ -1,5 +1,5 @@ name: ghc-exactprint -version: 1.7.0.0 +version: 1.7.0.1 synopsis: ExactPrint for GHC description: Using the API Annotations available from GHC 9.2.1, this library provides a means to round trip any code that can @@ -15,7 +15,8 @@ maintainer: alan.zimm@gmail.com category: Development build-type: Simple -tested-with: GHC == 9.6.1 +tested-with: GHC == 9.6.1, + GHC == 9.6.2 extra-source-files: ChangeLog tests/examples/failing/*.hs tests/examples/ghc710-only/*.hs diff --git a/src/Language/Haskell/GHC/ExactPrint/ExactPrint.hs b/src/Language/Haskell/GHC/ExactPrint/ExactPrint.hs --- a/src/Language/Haskell/GHC/ExactPrint/ExactPrint.hs +++ b/src/Language/Haskell/GHC/ExactPrint/ExactPrint.hs @@ -52,6 +52,7 @@ import GHC.Utils.Misc import GHC.Utils.Panic import qualified GHC.Data.Strict as Strict +import GHC.Base (NonEmpty(..)) import Language.Haskell.Syntax.Basic (FieldLabelString(..)) @@ -384,7 +385,7 @@ when (flush == NoFlushComments) $ do when ((getFollowingComments cs) /= []) $ do debugM $ "starting trailing comments:" ++ showAst (getFollowingComments cs) - mapM_ printOneComment (map tokComment $ getFollowingComments cs) + mapM_ printOneComment (concatMap tokComment $ getFollowingComments cs) debugM $ "ending trailing comments" let newAchor = anchor' { anchor_op = MovedAnchor edp } @@ -400,7 +401,7 @@ -- --------------------------------------------------------------------- addCommentsA :: (Monad m, Monoid w) => [LEpaComment] -> EP w m () -addCommentsA csNew = addComments (map tokComment csNew) +addCommentsA csNew = addComments (concatMap tokComment csNew) {- TODO: When we addComments, some may have an anchor that is no longer @@ -437,7 +438,7 @@ mapM_ printOneComment (sortComments cs) debugM $ "flushing comments:EOF:trailing:" ++ showAst (trailing) debugM $ "flushing comments:EOF:" ++ showAst (filterEofComment True trailing) - mapM_ printOneComment (map tokComment (filterEofComment True trailing)) + mapM_ printOneComment (concatMap tokComment (filterEofComment True trailing)) debugM $ "flushing comments done" filterEofComment :: Bool -> [LEpaComment] -> [LEpaComment] @@ -565,7 +566,7 @@ => CaptureComments -> EpaLocation -> String -> EP w m EpaLocation printStringAtAAC capture (EpaSpan r _) s = printStringAtRsC capture r s printStringAtAAC capture (EpaDelta d cs) s = do - mapM_ (printOneComment . tokComment) cs + mapM_ printOneComment $ concatMap tokComment cs pe1 <- getPriorEndD p1 <- getPosP printStringAtLsDelta d s @@ -1389,7 +1390,8 @@ exact hsmod@(HsModule {hsmodExt = XModulePs { hsmodAnn = EpAnnNotUsed }}) = withPpr hsmod >> return hsmod exact (HsModule (XModulePs an lo mdeprec mbDoc) mmn mexports imports decls) = do - mbDoc' <- markAnnotated mbDoc + let mbDoc' = mbDoc + -- mbDoc' <- markAnnotated mbDoc (an0, mmn' , mdeprec', mexports') <- case mmn of @@ -1529,10 +1531,27 @@ instance ExactPrint HsDocString where getAnnotationEntry _ = NoEntryVal setAnnotationAnchor a _ _ = a - exact ds = do - (printStringAdvance . exactPrintHsDocString) ds - return ds + exact (MultiLineDocString decorator (x :| xs)) = do + printStringAdvance ("-- " ++ printDecorator decorator) + pe <- getPriorEndD + debugM $ "MultiLineDocString: (pe,x)=" ++ showAst (pe,x) + x' <- markAnnotated x + xs' <- markAnnotated (map dedentDocChunk xs) + return (MultiLineDocString decorator (x' :| xs')) + exact x = do + -- TODO: can this happen? + debugM $ "Not exact printing:" ++ showAst x + return x + +instance ExactPrint HsDocStringChunk where + getAnnotationEntry _ = NoEntryVal + setAnnotationAnchor a _ _ = a + exact chunk = do + printStringAdvance ("--" ++ unpackHDSC chunk) + return chunk + + instance ExactPrint a => ExactPrint (WithHsDocIdentifiers a GhcPs) where getAnnotationEntry _ = NoEntryVal setAnnotationAnchor a _ _ = a @@ -1888,11 +1907,12 @@ getAnnotationEntry = const NoEntryVal setAnnotationAnchor a _ _ = a - exact v = case v of - (DocCommentNext ds) -> DocCommentNext <$> exact ds - (DocCommentPrev ds) -> DocCommentPrev <$> exact ds - (DocCommentNamed s ds) -> DocCommentNamed s <$> exact ds - (DocGroup i ds) -> DocGroup i <$> exact ds + exact v = return v + -- exact v = case v of + -- (DocCommentNext ds) -> DocCommentNext <$> exact ds + -- (DocCommentPrev ds) -> DocCommentPrev <$> exact ds + -- (DocCommentNamed s ds) -> DocCommentNamed s <$> exact ds + -- (DocGroup i ds) -> DocGroup i <$> exact ds -- --------------------------------------------------------------------- @@ -3922,8 +3942,8 @@ return (HsSpliceTy a splice') exact (HsDocTy an ty doc) = do ty' <- markAnnotated ty - doc' <- markAnnotated doc - return (HsDocTy an ty' doc') + -- doc' <- markAnnotated doc + return (HsDocTy an ty' doc) exact (HsBangTy an (HsSrcBang mt up str) ty) = do an0 <- case mt of @@ -4221,7 +4241,7 @@ , con_mb_cxt = mcxt , con_args = args , con_doc = doc }) = do - doc' <- mapM markAnnotated doc + -- doc' <- mapM markAnnotated doc an0 <- if has_forall then markEpAnnL an lidl AnnForall else return an @@ -4241,7 +4261,7 @@ , con_ex_tvs = ex_tvs' , con_mb_cxt = mcxt' , con_args = args' - , con_doc = doc' }) + , con_doc = doc }) where -- -- In ppr_details: let's not print the multiplicities (they are always 1, by @@ -4269,7 +4289,7 @@ , con_bndrs = bndrs , con_mb_cxt = mcxt, con_g_args = args , con_res_ty = res_ty, con_doc = doc }) = do - doc' <- mapM markAnnotated doc + -- doc' <- mapM markAnnotated doc cons' <- mapM markAnnotated cons dcol' <- markUniToken dcol an1 <- annotationsToComments an lidl [AnnOpenP, AnnCloseP] @@ -4298,7 +4318,7 @@ , con_dcolon = dcol' , con_bndrs = bndrs' , con_mb_cxt = mcxt', con_g_args = args' - , con_res_ty = res_ty', con_doc = doc' }) + , con_res_ty = res_ty', con_doc = doc }) -- --------------------------------------------------------------------- @@ -4334,8 +4354,8 @@ names' <- markAnnotated names an0 <- markEpAnnL an lidl AnnDcolon ftype' <- markAnnotated ftype - mdoc' <- mapM markAnnotated mdoc - return (ConDeclField an0 names' ftype' mdoc') + -- mdoc' <- mapM markAnnotated mdoc + return (ConDeclField an0 names' ftype' mdoc) -- --------------------------------------------------------------------- @@ -4533,7 +4553,14 @@ m' <- markAnnotated m return (IEModuleContents an0 m') - exact x = error $ "missing match for IE:" ++ showAst x + -- These three exist to not error out, but are no-ops The contents + -- appear as "normal" comments too, which we process instead. + exact (IEGroup x lev doc) = do + return (IEGroup x lev doc) + exact (IEDoc x doc) = do + return (IEDoc x doc) + exact (IEDocNamed x str) = do + return (IEDocNamed x str) -- --------------------------------------------------------------------- diff --git a/src/Language/Haskell/GHC/ExactPrint/Preprocess.hs b/src/Language/Haskell/GHC/ExactPrint/Preprocess.hs --- a/src/Language/Haskell/GHC/ExactPrint/Preprocess.hs +++ b/src/Language/Haskell/GHC/ExactPrint/Preprocess.hs @@ -126,8 +126,9 @@ goodComment :: GHC.LEpaComment -> Bool goodComment c = isGoodComment (tokComment c) where - isGoodComment :: Comment -> Bool - isGoodComment (Comment "" _ _ _) = False + isGoodComment :: [Comment] -> Bool + isGoodComment [] = False + isGoodComment [Comment "" _ _ _] = False isGoodComment _ = True diff --git a/src/Language/Haskell/GHC/ExactPrint/Utils.hs b/src/Language/Haskell/GHC/ExactPrint/Utils.hs --- a/src/Language/Haskell/GHC/ExactPrint/Utils.hs +++ b/src/Language/Haskell/GHC/ExactPrint/Utils.hs @@ -37,6 +37,7 @@ import GHC.Driver.Ppr import GHC.Data.FastString import qualified GHC.Data.Strict as Strict +import GHC.Base (NonEmpty(..)) import Debug.Trace import Language.Haskell.GHC.ExactPrint.Types @@ -214,9 +215,58 @@ ghcCommentText (L _ (GHC.EpaComment (EpaBlockComment s) _)) = s ghcCommentText (L _ (GHC.EpaComment (EpaEofComment) _)) = "" -tokComment :: LEpaComment -> Comment -tokComment t@(L lt c) = mkComment (normaliseCommentText $ ghcCommentText t) lt (ac_prior_tok c) +tokComment :: LEpaComment -> [Comment] +tokComment t@(L lt c) = + case c of + (GHC.EpaComment (EpaDocComment dc) pt) -> hsDocStringComments lt pt dc + _ -> [mkComment (normaliseCommentText (ghcCommentText t)) lt (ac_prior_tok c)] +hsDocStringComments :: Anchor -> RealSrcSpan -> GHC.HsDocString -> [Comment] +hsDocStringComments _ pt (MultiLineDocString dec (x :| xs)) = + let + decStr = printDecorator dec + L lx x' = dedentDocChunkBy (3 + length decStr) x + str = "-- " ++ decStr ++ unpackHDSC x' + docChunk _ [] = [] + docChunk pt' (L l chunk:cs) + = Comment ("--" ++ unpackHDSC chunk) (spanAsAnchor l) pt' Nothing : docChunk (rs l) cs + in + (Comment str (spanAsAnchor lx) pt Nothing : docChunk (rs lx) (map dedentDocChunk xs)) +hsDocStringComments anc pt (NestedDocString dec@(HsDocStringNamed _) (L _ chunk)) + = [Comment ("{- " ++ printDecorator dec ++ unpackHDSC chunk ++ "-}") anc pt Nothing ] +hsDocStringComments anc pt (NestedDocString dec (L _ chunk)) + = [Comment ("{-" ++ printDecorator dec ++ unpackHDSC chunk ++ "-}") anc pt Nothing ] + +hsDocStringComments _ _ (GeneratedDocString _) = [] -- Should not appear in user-written code + +-- Temporary until https://gitlab.haskell.org/ghc/ghc/-/issues/23459 is landed +-- At the moment the locations of the 'HsDocStringChunk's are from the start of +-- the string part, leaving aside the "--". So we need to subtract 2 columns from it +dedentDocChunk :: LHsDocStringChunk -> LHsDocStringChunk +dedentDocChunk chunk = dedentDocChunkBy 2 chunk + +dedentDocChunkBy :: Int -> LHsDocStringChunk -> LHsDocStringChunk +dedentDocChunkBy dedent (L (RealSrcSpan l mb) c) = L (RealSrcSpan l' mb) c + where + f = srcSpanFile l + sl = srcSpanStartLine l + sc = srcSpanStartCol l + el = srcSpanEndLine l + ec = srcSpanEndCol l + l' = mkRealSrcSpan (mkRealSrcLoc f sl (sc - dedent)) + (mkRealSrcLoc f el (ec - dedent)) + +dedentDocChunkBy _ x = x + +-- Temporary until https://gitlab.haskell.org/ghc/ghc/-/issues/23459 is landed +printDecorator :: HsDocStringDecorator -> String +printDecorator HsDocStringNext = "|" +printDecorator HsDocStringPrevious = "^" +printDecorator (HsDocStringNamed n) = '$':n +printDecorator (HsDocStringGroup n) = replicate n '*' + + + mkEpaComments :: [Comment] -> [Comment] -> EpAnnComments mkEpaComments priorCs [] = EpaComments (map comment2LEpaComment priorCs) @@ -235,9 +285,7 @@ -- Windows comments include \r in them from the lexer. normaliseCommentText :: String -> String -normaliseCommentText [] = [] -normaliseCommentText ('\r':xs) = normaliseCommentText xs -normaliseCommentText (x:xs) = x:normaliseCommentText xs +normaliseCommentText = filter (/= '\r') -- |Must compare without span filenames, for CPP injected comments with fake filename cmpComments :: Comment -> Comment -> Ordering diff --git a/tests/Test.hs b/tests/Test.hs --- a/tests/Test.hs +++ b/tests/Test.hs @@ -247,7 +247,11 @@ -- mkParserTest libdir "ghc96" "T11671_run.hs" -- mkParserTest libdir "ghc96" "LexerM.hs" - mkParserTestBC libdir "ghc96" "LexerM.hs" + -- mkParserTestBC libdir "ghc96" "LexerM.hs" + + -- mkParserTest libdir "ghc94" "Haddock.hs" + -- mkParserTest libdir "ghc94" "Haddock1.hs" + mkParserTestBC libdir "ghc94" "Haddock1.hs" -- Needs GHC changes diff --git a/tests/Test/NoAnnotations.hs b/tests/Test/NoAnnotations.hs --- a/tests/Test/NoAnnotations.hs +++ b/tests/Test/NoAnnotations.hs @@ -89,7 +89,7 @@ runPrettyRoundTrip libdir origFile !parsedOrig _cs = do let priorComments = GHC.priorComments $ GHC.epAnnComments $ GHC.hsmodAnn $ GHC.hsmodExt $ GHC.unLoc parsedOrig - let comments = map tokComment priorComments + let comments = concatMap tokComment priorComments let pragmas = filter (\(Comment c _ _ _) -> isPrefixOf "{-#" c ) comments let pragmaStr = intercalate "\n" $ map commentContents pragmas diff --git a/tests/examples/ghc94/Haddock.hs b/tests/examples/ghc94/Haddock.hs new file mode 100644 --- /dev/null +++ b/tests/examples/ghc94/Haddock.hs @@ -0,0 +1,408 @@ +{-# OPTIONS_GHC -fno-warn-redundant-constraints -haddock #-} +----------------------------------------------------------------------------- +-- | +-- Module : Test +-- Copyright : (c) Simon Marlow 2002 +-- License : BSD-style +-- +-- Maintainer : libraries@haskell.org +-- Stability : provisional +-- Portability : portable +-- +-- This module illustrates & tests most of the features of Haddock. +-- Testing references from the description: 'T', 'f', 'g', 'Visible.visible'. +-- +----------------------------------------------------------------------------- + +-- This is plain comment, ignored by Haddock. + +module Haddock ( + + -- Section headings are introduced with '-- *': + -- * Type declarations + + -- Subsection headings are introduced with '-- **' and so on. + -- ** Data types + T(..), T2, T3(..), T4(..), T5(..), T6(..), + N1(..), N2(..), N3(..), N4, N5(..), N6(..), N7(..), + + -- ** Records + R(..), R1(..), + + -- | test that we can export record selectors on their own: + p, q, u, + + -- * Class declarations + C(a,b), D(..), E, F(..), + + -- | Test that we can export a class method on its own: + a, + + -- * Function types + f, g, + + -- * Auxiliary stuff + + -- $aux1 + + -- $aux2 + + -- $aux3 + + -- $aux4 + + -- $aux5 + + -- $aux6 + + -- $aux7 + + -- $aux8 + + -- $aux9 + + -- $aux10 + + -- $aux11 + + -- $aux12 + + -- | This is some inline documentation in the export list + -- + -- > a code block using bird-tracks + -- > each line must begin with > (which isn't significant unless it + -- > is at the beginning of the line). + + -- * A hidden module + module Hidden, + + -- * A visible module + module Visible, + + {-| nested-style doc comments -} + + -- * Existential \/ Universal types + Ex(..), + + -- * Type signatures with argument docs + k, l, m, o, + + -- * A section + -- and without an intervening comma: + -- ** A subsection + +{-| + > a literal line + + $ a non /literal/ line $ +-} + + f', + ) where + +import Hidden +import Visible + +-- | This comment applies to the /following/ declaration +-- and it continues until the next non-comment line +data T a b + = A Int (Maybe Float) -- ^ This comment describes the 'A' constructor + | -- | This comment describes the 'B' constructor + B (T a b, T Int Float) -- ^ + +-- | An abstract data declaration +data T2 a b = T2 a b + +-- | A data declaration with no documentation annotations on the constructors +data T3 a b = A1 a | B1 b + +-- A data declaration with no documentation annotations at all +data T4 a b = A2 a | B2 b + +-- A data declaration documentation on the constructors only +data T5 a b + = A3 a -- ^ documents 'A3' + | B3 b -- ^ documents 'B3' + +-- | Testing alternative comment styles +data T6 + -- | This is the doc for 'A4' + = A4 + | B4 + | -- ^ This is the doc for 'B4' + + -- | This is the doc for 'C4' + C4 + +-- | A newtype +newtype N1 a = N1 a + +-- | A newtype with a fieldname +newtype N2 a b = N2 {n :: a b} + +-- | A newtype with a fieldname, documentation on the field +newtype N3 a b = N3 {n3 :: a b -- ^ this is the 'n3' field + } + +-- | An abstract newtype - we show this one as data rather than newtype because +-- the difference isn\'t visible to the programmer for an abstract type. +newtype N4 a b = N4 a + +newtype N5 a b = N5 {n5 :: a b -- ^ no docs on the datatype or the constructor + } + +newtype N6 a b = N6 {n6 :: a b + } + -- ^ docs on the constructor only + +-- | docs on the newtype and the constructor +newtype N7 a b = N7 {n7 :: a b + } + -- ^ The 'N7' constructor + + +class (D a) => C a where + -- |this is a description of the 'a' method + a :: IO a + b :: [a] + -- ^ this is a description of the 'b' method + c :: a -- c is hidden in the export list + +-- ^ This comment applies to the /previous/ declaration (the 'C' class) + +class D a where + d :: T a b + e :: (a,a) +-- ^ This is a class declaration with no separate docs for the methods + +instance D Int where + d = undefined + e = undefined + +-- instance with a qualified class name +instance Test.D Float where + d = undefined + e = undefined + +class E a where + ee :: a +-- ^ This is a class declaration with no methods (or no methods exported) + +-- This is a class declaration with no documentation at all +class F a where + ff :: a + +-- | This is the documentation for the 'R' record, which has four fields, +-- 'p', 'q', 'r', and 's'. +data R = + -- | This is the 'C1' record constructor, with the following fields: + C1 { p :: Int -- ^ This comment applies to the 'p' field + , q :: forall a . a->a -- ^ This comment applies to the 'q' field + , -- | This comment applies to both 'r' and 's' + r,s :: Int + } + | C2 { t :: T1 -> (T2 Int Int)-> (T3 Bool Bool) -> (T4 Float Float) -> T5 () (), + u,v :: Int + } + -- ^ This is the 'C2' record constructor, also with some fields: + +-- | Testing different record commenting styles +data R1 + -- | This is the 'C3' record constructor + = C3 { + -- | The 's1' record selector + s1 :: Int + -- | The 's2' record selector + , s2 :: Int + , s3 :: Int -- NOTE: In the original examples/Test.hs in Haddock, there is an extra "," here. + -- Since GHC doesn't allow that, I have removed it in this file. + -- ^ The 's3' record selector + } + +-- These section headers are only used when there is no export list to +-- give the structure of the documentation: + +-- * This is a section header (level 1) +-- ** This is a section header (level 2) +-- *** This is a section header (level 3) + +{-| +In a comment string we can refer to identifiers in scope with +single quotes like this: 'T', and we can refer to modules by +using double quotes: "Foo". We can add emphasis /like this/. + + * This is a bulleted list + + - This is the next item (different kind of bullet) + + (1) This is an ordered list + + 2. This is the next item (different kind of bullet) + +@ + This is a block of code, which can include other markup: 'R' + formatting + is + significant +@ + +> this is another block of code + +We can also include URLs in documentation: . +-} + +f :: C a => a -> Int + +-- | we can export foreign declarations too +foreign import ccall "header.h" g :: Int -> IO CInt + +-- | this doc string has a parse error in it: \' +h :: Int +h = 42 + + +-- $aux1 This is some documentation that is attached to a name ($aux1) +-- rather than a source declaration. The documentation may be +-- referred to in the export list using its name. +-- +-- @ code block in named doc @ + +-- $aux2 This is some documentation that is attached to a name ($aux2) + +-- $aux3 +-- @ code block on its own in named doc @ + +-- $aux4 +-- +-- @ code block on its own in named doc (after newline) @ + +{- $aux5 a nested, named doc comment + + with a paragraph, + + @ and a code block @ +-} + +-- some tests for various arrangements of code blocks: + +{- $aux6 +>test +>test1 + +@ test2 + test3 +@ +-} + +{- $aux7 +@ +test1 +test2 +@ +-} + +{- $aux8 +>test3 +>test4 +-} + +{- $aux9 +@ +test1 +test2 +@ + +>test3 +>test4 +-} + +{- $aux10 +>test3 +>test4 + +@ +test1 +test2 +@ +-} + +-- This one is currently wrong (Haddock 0.4). The @...@ part is +-- interpreted as part of the bird-tracked code block. +{- $aux11 +aux11: + +>test3 +>test4 + +@ +test1 +test2 +@ +-} + +-- $aux12 +-- > foo +-- +-- > bar +-- + +-- | A data-type using existential\/universal types +data Ex a + = forall b . C b => Ex1 b + | forall b . Ex2 b + | forall b . C a => Ex3 b -- NOTE: I have added "forall b" here make GHC accept this file + | Ex4 (forall a . a -> a) + +-- | This is a function with documentation for each argument +k :: T () () -- ^ This argument has type 'T' + -> (T2 Int Int) -- ^ This argument has type 'T2 Int Int' + -> (T3 Bool Bool -> T4 Float Float) -- ^ This argument has type @T3 Bool Bool -> T4 Float Float@ + -> T5 () () -- ^ This argument has a very long description that should + -- hopefully cause some wrapping to happen when it is finally + -- rendered by Haddock in the generated HTML page. + -> IO () -- ^ This is the result type + +-- This function has arg docs but no docs for the function itself +l :: (Int, Int, Float) -- ^ takes a triple + -> Int -- ^ returns an 'Int' + +-- | This function has some arg docs +m :: R + -> N1 () -- ^ one of the arguments + -> IO Int -- ^ and the return value + +-- | This function has some arg docs but not a return value doc + +-- can't use the original name ('n') with GHC +newn :: R -- ^ one of the arguments, an 'R' + -> N1 () -- ^ one of the arguments + -> IO Int +newn = undefined + + +-- | A foreign import with argument docs +foreign import ccall unsafe "header.h" + o :: Float -- ^ The input float + -> IO Float -- ^ The output float + +-- | We should be able to escape this: \#\#\# + +-- p :: Int +-- can't use the above original definition with GHC +newp :: Int +newp = undefined + +-- | a function with a prime can be referred to as 'f'' +-- but f' doesn't get link'd 'f\'' +f' :: Int + + +-- Add some definitions here so that this file can be compiled with GHC + +data T1 +f = undefined +f' = undefined +type CInt = Int +k = undefined +l = undefined +m = undefined diff --git a/tests/examples/ghc94/Haddock1.hs b/tests/examples/ghc94/Haddock1.hs new file mode 100644 --- /dev/null +++ b/tests/examples/ghc94/Haddock1.hs @@ -0,0 +1,33 @@ +{-# OPTIONS_GHC -fno-warn-redundant-constraints -haddock #-} +-- | Haddock comment, +-- coming before the module +module Haddock1 ( + + -- | This is some inline documentation in the export list + -- + -- > a code block using bird-tracks + -- > each line must begin with > (which isn't significant unless it + -- > is at the beginning of the line). + f + + {-| nested-style doc comments -} + , g + + -- * A section + -- and without an intervening comma: + -- ** A subsection + ) where + +-- | Haddock before imports +import Data.List + +-- | Haddock before decl +f = undefined +g = undefined + +-- | This comment applies to the /following/ declaration +-- and it continues until the next non-comment line +data T a b + = A Int (Maybe Float) -- ^ This comment describes the 'A' constructor + | -- | This comment describes the 'B' constructor + B (T a b, T Int Float) -- ^