brittany/src/Language/Haskell/Brittany/Internal/Transformations/Alt.hs

953 lines
44 KiB
Haskell

#define INSERTTRACESALT 0
#define INSERTTRACESALTVISIT 0
#define INSERTTRACESGETSPACING 0
{-# LANGUAGE TypeOperators #-}
{-# LANGUAGE BangPatterns #-}
{-# LANGUAGE DataKinds #-}
module Language.Haskell.Brittany.Internal.Transformations.Alt
( transformAlts
)
where
#include "prelude.inc"
import Data.HList.ContainsType
import Language.Haskell.Brittany.Internal.Utils
import Language.Haskell.Brittany.Internal.Config.Types
import Language.Haskell.Brittany.Internal.Types
import qualified Control.Monad.Memo as Memo
data AltCurPos = AltCurPos
{ _acp_line :: Int -- chars in the current line
, _acp_indent :: Int -- current indentation level
, _acp_indentPrep :: Int -- indentChange affecting the next Par
, _acp_forceMLFlag :: AltLineModeState
}
deriving (Show)
data AltLineModeState
= AltLineModeStateNone
| AltLineModeStateForceML Bool -- true ~ decays on next wrap
| AltLineModeStateForceSL
| AltLineModeStateContradiction
-- i.e. ForceX False -> ForceX True -> None
deriving (Show)
altLineModeRefresh :: AltLineModeState -> AltLineModeState
altLineModeRefresh AltLineModeStateNone = AltLineModeStateNone
altLineModeRefresh AltLineModeStateForceML{} = AltLineModeStateForceML False
altLineModeRefresh AltLineModeStateForceSL = AltLineModeStateForceSL
altLineModeRefresh AltLineModeStateContradiction = AltLineModeStateContradiction
altLineModeDecay :: AltLineModeState -> AltLineModeState
altLineModeDecay AltLineModeStateNone = AltLineModeStateNone
altLineModeDecay (AltLineModeStateForceML False) = AltLineModeStateForceML True
altLineModeDecay (AltLineModeStateForceML True ) = AltLineModeStateNone
altLineModeDecay AltLineModeStateForceSL = AltLineModeStateForceSL
altLineModeDecay AltLineModeStateContradiction = AltLineModeStateContradiction
mergeLineMode :: AltCurPos -> AltLineModeState -> AltCurPos
mergeLineMode acp s = case (_acp_forceMLFlag acp, s) of
(AltLineModeStateContradiction, _) -> acp
(AltLineModeStateNone, x) -> acp { _acp_forceMLFlag = x }
(AltLineModeStateForceSL, AltLineModeStateForceSL) -> acp
(AltLineModeStateForceML{}, AltLineModeStateForceML{}) ->
acp { _acp_forceMLFlag = s }
_ -> acp { _acp_forceMLFlag = AltLineModeStateContradiction }
-- removes any BDAlt's from the BriDoc
transformAlts
:: forall r w s
. ( Data.HList.ContainsType.ContainsType Config r
, Data.HList.ContainsType.ContainsType (Seq String) w
)
=> BriDocNumbered
-> MultiRWSS.MultiRWS r w s BriDoc
transformAlts =
MultiRWSS.withMultiStateA (AltCurPos 0 0 0 AltLineModeStateNone)
. Memo.startEvalMemoT
. fmap unwrapBriDocNumbered
. rec
where
-- this function is exponential by nature and cannot be improved in any
-- way i can think of, and i've tried. (stupid StableNames.)
-- transWrap :: BriDoc -> BriDocNumbered
-- transWrap brDc = flip StateS.evalState (1::Int)
-- $ Memo.startEvalMemoT
-- $ go brDc
-- where
-- incGet = StateS.get >>= \i -> StateS.put (i+1) $> i
-- go :: BriDoc -> Memo.MemoT BriDoc BriDocNumbered (StateS.State Int) BriDocNumbered
-- go = Memo.memo $ \bdX -> do
-- i <- lift $ incGet
-- fmap (\bd' -> (i,bd')) $ case bdX of
-- BDEmpty -> return $ BDFEmpty
-- BDLit t -> return $ BDFLit t
-- BDSeq list -> BDFSeq <$> go `mapM` list
-- BDCols sig list -> BDFCols sig <$> go `mapM` list
-- BDSeparator -> return $ BDFSeparator
-- BDAddBaseY ind bd -> BDFAddBaseY ind <$> go bd
-- BDSetBaseY bd -> BDFSetBaseY <$> go bd
-- BDSetIndentLevel bd -> BDFSetIndentLevel <$> go bd
-- BDPar ind line indented -> [ BDFPar ind line' indented'
-- | line' <- go line
-- , indented' <- go indented
-- ]
-- BDAlt alts -> BDFAlt <$> go `mapM` alts -- not that this will happen
-- BDForceMultiline bd -> BDFForceMultiline <$> go bd
-- BDForceSingleline bd -> BDFForceSingleline <$> go bd
-- BDForwardLineMode bd -> BDFForwardLineMode <$> go bd
-- BDExternal k ks c t -> return $ BDFExternal k ks c t
-- BDAnnotationPrior annKey bd -> BDFAnnotationPrior annKey <$> go bd
-- BDAnnotationPost annKey bd -> BDFAnnotationRest annKey <$> go bd
-- BDLines lines -> BDFLines <$> go `mapM` lines
-- BDEnsureIndent ind bd -> BDFEnsureIndent ind <$> go bd
-- BDProhibitMTEL bd -> BDFProhibitMTEL <$> go bd
rec :: BriDocNumbered -> Memo.MemoT Int [VerticalSpacing] (MultiRWSS.MultiRWS r w (AltCurPos ': s)) BriDocNumbered
rec bdX@(brDcId, brDc) = do
#if INSERTTRACESALTVISIT
do
acp :: AltCurPos <- mGet
tellDebugMess $ "transformAlts: visiting: " ++ case brDc of
BDFAnnotationPrior annKey _ -> show (toConstr brDc, annKey, acp)
BDFAnnotationRest annKey _ -> show (toConstr brDc, annKey, acp)
_ -> show (toConstr brDc, acp)
#endif
let reWrap = (,) brDcId
-- debugAcp :: AltCurPos <- mGet
case brDc of
-- BDWrapAnnKey annKey bd -> do
-- acp <- mGet
-- mSet $ acp { _acp_forceMLFlag = altLineModeDecay $ _acp_forceMLFlag acp }
-- BDWrapAnnKey annKey <$> rec bd
BDFEmpty{} -> processSpacingSimple bdX $> bdX
BDFLit{} -> processSpacingSimple bdX $> bdX
BDFSeq list ->
reWrap . BDFSeq <$> list `forM` rec
BDFCols sig list ->
reWrap . BDFCols sig <$> list `forM` rec
BDFSeparator -> processSpacingSimple bdX $> bdX
BDFAddBaseY indent bd -> do
acp <- mGet
indAdd <- fixIndentationForMultiple acp indent
mSet $ acp { _acp_indentPrep = max (_acp_indentPrep acp) indAdd }
r <- rec bd
acp' <- mGet
mSet $ acp' { _acp_indent = _acp_indent acp }
return $ case indent of
BrIndentNone -> r
BrIndentRegular -> reWrap $ BDFAddBaseY (BrIndentSpecial indAdd) r
BrIndentSpecial i -> reWrap $ BDFAddBaseY (BrIndentSpecial i) r
BDFBaseYPushCur bd -> do
acp <- mGet
mSet $ acp { _acp_indent = _acp_line acp }
r <- rec bd
return $ reWrap $ BDFBaseYPushCur r
BDFBaseYPop bd -> do
acp <- mGet
r <- rec bd
acp' <- mGet
mSet $ acp' { _acp_indent = _acp_indentPrep acp }
return $ reWrap $ BDFBaseYPop r
BDFIndentLevelPushCur bd -> do
reWrap . BDFIndentLevelPushCur <$> rec bd
BDFIndentLevelPop bd -> do
reWrap . BDFIndentLevelPop <$> rec bd
BDFPar indent sameLine indented -> do
indAmount <- mAsk <&> _conf_layout .> _lconfig_indentAmount .> confUnpack
let indAdd = case indent of
BrIndentNone -> 0
BrIndentRegular -> indAmount
BrIndentSpecial i -> i
acp <- mGet
let ind = _acp_indent acp + _acp_indentPrep acp + indAdd
mSet $ acp
{ _acp_indent = ind
, _acp_indentPrep = 0
}
sameLine' <- rec sameLine
mModify $ \acp' -> acp'
{ _acp_line = ind
, _acp_indent = ind
}
indented' <- rec indented
return $ reWrap $ BDFPar indent sameLine' indented'
BDFAlt [] -> error "empty BDAlt" -- returning BDEmpty instead is a
-- possibility, but i will prefer a
-- fail-early approach; BDEmpty does not
-- make sense semantically for Alt[].
BDFAlt alts -> do
altChooser <- mAsk <&> _conf_layout .> _lconfig_altChooser .> confUnpack
case altChooser of
AltChooserSimpleQuick -> do
rec $ head alts
AltChooserShallowBest -> do
spacings <- alts `forM` getSpacing
acp <- mGet
let lineCheck LineModeInvalid = False
lineCheck (LineModeValid (VerticalSpacing _ p _)) =
case _acp_forceMLFlag acp of
AltLineModeStateNone -> True
AltLineModeStateForceSL{} -> p == VerticalSpacingParNone
AltLineModeStateForceML{} -> p /= VerticalSpacingParNone
AltLineModeStateContradiction -> False
-- TODO: use COMPLETE pragma instead?
lineCheck _ = error "ghc exhaustive check is insufficient"
lconf <- _conf_layout <$> mAsk
#if INSERTTRACESALT
tellDebugMess $ "considering options with " ++ show (length alts, acp)
#endif
let options = -- trace ("considering options:" ++ show (length alts, acp)) $
(zip spacings alts
<&> \(vs, bd) -> -- trace ("spacing=" ++ show vs ++ ",hasSpace=" ++ show (hasSpace lconf acp vs) ++ ",lineCheck=" ++ show (lineCheck vs))
( hasSpace1 lconf acp vs && lineCheck vs, bd))
#if INSERTTRACESALT
zip spacings options `forM_` \(vs, (_, bd)) ->
tellDebugMess $ " " ++ "spacing=" ++ show vs
++ ",hasSpace1=" ++ show (hasSpace1 lconf acp vs)
++ ",lineCheck=" ++ show (lineCheck vs)
++ " " ++ show (toConstr bd)
#endif
id -- - $ (fmap $ \x -> traceShow (briDocToDoc x) x)
$ rec
$ fromMaybe (-- trace ("choosing last") $
List.last alts)
$ Data.List.Extra.firstJust (\(_i::Int, (b,x)) ->
[ -- traceShow ("choosing option " ++ show i) $
x
| b
])
$ zip [1..] options
AltChooserBoundedSearch limit -> do
spacings <- alts `forM` getSpacings limit
acp <- mGet
let lineCheck (VerticalSpacing _ p _) =
case _acp_forceMLFlag acp of
AltLineModeStateNone -> True
AltLineModeStateForceSL{} -> p == VerticalSpacingParNone
AltLineModeStateForceML{} -> p /= VerticalSpacingParNone
AltLineModeStateContradiction -> False
lconf <- _conf_layout <$> mAsk
#if INSERTTRACESALT
tellDebugMess $ "considering options with " ++ show (length alts, acp)
#endif
let options = -- trace ("considering options:" ++ show (length alts, acp)) $
(zip spacings alts
<&> \(vs, bd) -> -- trace ("spacing=" ++ show vs ++ ",hasSpace=" ++ show (hasSpace lconf acp vs) ++ ",lineCheck=" ++ show (lineCheck vs))
( any (hasSpace2 lconf acp) vs
&& any lineCheck vs, bd))
let checkedOptions :: [Maybe (Int, BriDocNumbered)] =
zip [1..] options <&> (\(i, (b,x)) -> [ (i, x) | b ])
#if INSERTTRACESALT
zip spacings options `forM_` \(vs, (_, bd)) ->
tellDebugMess $ " " ++ "spacing=" ++ show vs
++ ",hasSpace2=" ++ show (hasSpace2 lconf acp <$> vs)
++ ",lineCheck=" ++ show (lineCheck <$> vs)
++ " " ++ show (toConstr bd)
tellDebugMess $ " " ++ show (Data.Maybe.mapMaybe (fmap fst) checkedOptions)
#endif
id -- - $ (fmap $ \x -> traceShow (briDocToDoc x) x)
$ rec
$ fromMaybe (-- trace ("choosing last") $
List.last alts)
$ Data.List.Extra.firstJust (fmap snd) checkedOptions
BDFForceMultiline bd -> do
acp <- mGet
x <- do
mSet $ mergeLineMode acp (AltLineModeStateForceML False)
rec bd
acp' <- mGet
mSet $ acp' { _acp_forceMLFlag = _acp_forceMLFlag acp }
return $ x
BDFForceSingleline bd -> do
acp <- mGet
x <- do
mSet $ mergeLineMode acp AltLineModeStateForceSL
rec bd
acp' <- mGet
mSet $ acp' { _acp_forceMLFlag = _acp_forceMLFlag acp }
return $ x
BDFForwardLineMode bd -> do
acp <- mGet
x <- do
mSet $ acp { _acp_forceMLFlag = altLineModeRefresh $ _acp_forceMLFlag acp }
rec bd
acp' <- mGet
mSet $ acp' { _acp_forceMLFlag = _acp_forceMLFlag acp }
return $ x
BDFExternal{} -> processSpacingSimple bdX $> bdX
BDFPlain{} -> processSpacingSimple bdX $> bdX
BDFAnnotationPrior annKey bd -> do
acp <- mGet
mSet $ acp { _acp_forceMLFlag = altLineModeDecay $ _acp_forceMLFlag acp }
bd' <- rec bd
return $ reWrap $ BDFAnnotationPrior annKey bd'
BDFAnnotationRest annKey bd ->
reWrap . BDFAnnotationRest annKey <$> rec bd
BDFAnnotationKW annKey kw bd ->
reWrap . BDFAnnotationKW annKey kw <$> rec bd
BDFMoveToKWDP annKey kw b bd ->
reWrap . BDFMoveToKWDP annKey kw b <$> rec bd
BDFLines [] -> return $ reWrap BDFEmpty -- evil transformation. or harmless.
BDFLines (l:lr) -> do
ind <- _acp_indent <$> mGet
l' <- rec l
lr' <- lr `forM` \x -> do
mModify $ \acp -> acp
{ _acp_line = ind
, _acp_indent = ind
}
rec x
return $ reWrap $ BDFLines (l':lr')
BDFEnsureIndent indent bd -> do
acp <- mGet
indAdd <- fixIndentationForMultiple acp indent
mSet $ acp
{ _acp_indentPrep = 0
-- TODO: i am not sure this is valid, in general.
, _acp_indent = _acp_indent acp + indAdd
, _acp_line = max (_acp_line acp) (_acp_indent acp + indAdd)
-- we cannot use just _acp_line acp + indAdd because of the case
-- where there are multiple BDFEnsureIndents in the same line.
-- Then, the actual indentation is relative to the current
-- indentation, not the current cursor position.
}
r <- rec bd
acp' <- mGet
mSet $ acp' { _acp_indent = _acp_indent acp }
return $ case indent of
BrIndentNone -> r
BrIndentRegular -> reWrap $ BDFEnsureIndent (BrIndentSpecial indAdd) r
BrIndentSpecial i -> reWrap $ BDFEnsureIndent (BrIndentSpecial i) r
BDFNonBottomSpacing _ bd -> rec bd
BDFSetParSpacing bd -> rec bd
BDFForceParSpacing bd -> rec bd
BDFDebug s bd -> do
acp :: AltCurPos <- mGet
tellDebugMess $ "transformAlts: BDFDEBUG " ++ s ++ " (node-id=" ++ show brDcId ++ "): acp=" ++ show acp
reWrap . BDFDebug s <$> rec bd
processSpacingSimple
:: ( MonadMultiReader Config m
, MonadMultiState AltCurPos m
, MonadMultiWriter (Seq String) m
)
=> BriDocNumbered
-> m ()
processSpacingSimple bd = getSpacing bd >>= \case
LineModeInvalid -> error "processSpacingSimple inv"
LineModeValid (VerticalSpacing i VerticalSpacingParNone _) -> do
acp <- mGet
mSet $ acp { _acp_line = _acp_line acp + i }
LineModeValid (VerticalSpacing _ _ _) -> error "processSpacingSimple par"
_ -> error "ghc exhaustive check is insufficient"
hasSpace1 :: LayoutConfig -> AltCurPos -> LineModeValidity VerticalSpacing -> Bool
hasSpace1 _ _ LineModeInvalid = False
hasSpace1 lconf acp (LineModeValid vs) = hasSpace2 lconf acp vs
hasSpace1 _ _ _ = error "ghc exhaustive check is insufficient"
hasSpace2 :: LayoutConfig -> AltCurPos -> VerticalSpacing -> Bool
hasSpace2 lconf (AltCurPos line _indent _ _) (VerticalSpacing sameLine VerticalSpacingParNone _)
= line + sameLine <= confUnpack (_lconfig_cols lconf)
hasSpace2 lconf (AltCurPos line indent indentPrep _) (VerticalSpacing sameLine (VerticalSpacingParSome par) _)
= line + sameLine <= confUnpack (_lconfig_cols lconf)
&& indent + indentPrep + par <= confUnpack (_lconfig_cols lconf)
hasSpace2 lconf (AltCurPos line _indent _ _) (VerticalSpacing sameLine VerticalSpacingParAlways{} _)
= line + sameLine <= confUnpack (_lconfig_cols lconf)
getSpacing
:: forall m
. (MonadMultiReader Config m, MonadMultiWriter (Seq String) m)
=> BriDocNumbered
-> m (LineModeValidity VerticalSpacing)
getSpacing !bridoc = rec bridoc
where
rec :: BriDocNumbered -> m (LineModeValidity VerticalSpacing)
rec (brDcId, brDc) = do
config <- mAsk
let colMax = config & _conf_layout & _lconfig_cols & confUnpack
result <- case brDc of
-- BDWrapAnnKey _annKey bd -> rec bd
BDFEmpty ->
return $ LineModeValid $ VerticalSpacing 0 VerticalSpacingParNone False
BDFLit t ->
return $ LineModeValid $ VerticalSpacing (Text.length t) VerticalSpacingParNone False
BDFSeq list ->
sumVs <$> rec `mapM` list
BDFCols _sig list -> sumVs <$> rec `mapM` list
BDFSeparator ->
return $ LineModeValid $ VerticalSpacing 1 VerticalSpacingParNone False
BDFAddBaseY indent bd -> do
mVs <- rec bd
return $ mVs <&> \vs -> vs
{ _vs_paragraph = case _vs_paragraph vs of
VerticalSpacingParNone -> VerticalSpacingParNone
VerticalSpacingParAlways i -> VerticalSpacingParAlways $ case indent of
BrIndentNone -> i
BrIndentRegular -> i + ( confUnpack
$ _lconfig_indentAmount
$ _conf_layout
$ config
)
BrIndentSpecial j -> i + j
VerticalSpacingParSome i -> VerticalSpacingParSome $ case indent of
BrIndentNone -> i
BrIndentRegular -> i + ( confUnpack
$ _lconfig_indentAmount
$ _conf_layout
$ config
)
BrIndentSpecial j -> i + j
}
BDFBaseYPushCur bd -> do
mVs <- rec bd
return $ mVs <&> \vs -> vs
-- We leave par as-is, even though it technically is not
-- accurate (in general).
-- the reason is that we really want to _keep_ it Just if it is
-- just so we properly communicate the is-multiline fact.
-- An alternative would be setting to (Just 0).
{ _vs_sameLine = max (_vs_sameLine vs)
(case _vs_paragraph vs of
VerticalSpacingParNone -> 0
VerticalSpacingParSome i -> i
VerticalSpacingParAlways i -> min colMax i)
, _vs_paragraph = VerticalSpacingParSome 0
}
BDFBaseYPop bd -> rec bd
BDFIndentLevelPushCur bd -> rec bd
BDFIndentLevelPop bd -> rec bd
BDFPar BrIndentNone sameLine indented -> do
mVs <- rec sameLine
mIndSp <- rec indented
return
$ [ VerticalSpacing lsp pspResult parFlagResult
| VerticalSpacing lsp mPsp _ <- mVs
, indSp <- mIndSp
, lineMax <- getMaxVS $ mIndSp
, let pspResult = case mPsp of
VerticalSpacingParSome psp -> VerticalSpacingParSome $ max psp lineMax
VerticalSpacingParNone -> VerticalSpacingParSome $ lineMax
VerticalSpacingParAlways psp -> VerticalSpacingParAlways $ max psp lineMax
, let parFlagResult = mPsp == VerticalSpacingParNone
&& _vs_paragraph indSp == VerticalSpacingParNone
&& _vs_parFlag indSp
]
BDFPar{} -> error "BDPar with indent in getSpacing"
BDFAlt [] -> error "empty BDAlt"
BDFAlt (alt:_) -> rec alt
BDFForceMultiline bd -> do
mVs <- rec bd
return $ mVs >>= _vs_paragraph .> \case
VerticalSpacingParNone -> LineModeInvalid
_ -> mVs
BDFForceSingleline bd -> do
mVs <- rec bd
return $ mVs >>= _vs_paragraph .> \case
VerticalSpacingParNone -> mVs
_ -> LineModeInvalid
BDFForwardLineMode bd -> rec bd
BDFExternal _ _ _ txt -> return $ LineModeValid $ case Text.lines txt of
[t] -> VerticalSpacing (Text.length t) VerticalSpacingParNone False
_ -> VerticalSpacing 999 VerticalSpacingParNone False
BDFPlain txt -> return $ LineModeValid $ case Text.lines txt of
[t] -> VerticalSpacing (Text.length t) VerticalSpacingParNone False
_ -> VerticalSpacing 999 VerticalSpacingParNone False
BDFAnnotationPrior _annKey bd -> rec bd
BDFAnnotationKW _annKey _kw bd -> rec bd
BDFAnnotationRest _annKey bd -> rec bd
BDFMoveToKWDP _annKey _kw _b bd -> rec bd
BDFLines [] -> return
$ LineModeValid
$ VerticalSpacing 0 VerticalSpacingParNone False
BDFLines ls@(_:_) -> do
lSps <- rec `mapM` ls
let (mVs:_) = lSps -- separated into let to avoid MonadFail
return $ [ VerticalSpacing lsp (VerticalSpacingParSome $ lineMax) False
| VerticalSpacing lsp _ _ <- mVs
, lineMax <- getMaxVS $ maxVs $ lSps
]
BDFEnsureIndent indent bd -> do
mVs <- rec bd
let addInd = case indent of
BrIndentNone -> 0
BrIndentRegular -> confUnpack
$ _lconfig_indentAmount
$ _conf_layout
$ config
BrIndentSpecial i -> i
return $ mVs <&> \(VerticalSpacing lsp psp pf) ->
VerticalSpacing (lsp + addInd) psp pf
BDFNonBottomSpacing b bd -> do
mVs <- rec bd
return
$ mVs
<|> LineModeValid
(VerticalSpacing
0
(if b then VerticalSpacingParSome 0
else VerticalSpacingParAlways colMax
)
False
)
BDFSetParSpacing bd -> do
mVs <- rec bd
return $ mVs <&> \vs -> vs { _vs_parFlag = True }
BDFForceParSpacing bd -> do
mVs <- rec bd
return $ [ vs | vs <- mVs, _vs_parFlag vs || _vs_paragraph vs == VerticalSpacingParNone ]
BDFDebug s bd -> do
r <- rec bd
tellDebugMess $ "getSpacing: BDFDebug " ++ show s ++ " (node-id=" ++ show brDcId ++ "): mVs=" ++ show r
return r
#if INSERTTRACESGETSPACING
tellDebugMess $ "getSpacing: visiting: " ++ show (toConstr $ brDc) ++ " -> " ++ show result
#endif
return result
maxVs :: [LineModeValidity VerticalSpacing] -> LineModeValidity VerticalSpacing
maxVs = foldl'
(liftM2 (\(VerticalSpacing x1 x2 _) (VerticalSpacing y1 y2 _) ->
VerticalSpacing (max x1 y1) (case (x2, y2) of
(x, VerticalSpacingParNone) -> x
(VerticalSpacingParNone, x) -> x
(VerticalSpacingParAlways i, VerticalSpacingParAlways j) ->
VerticalSpacingParAlways $ max i j
(VerticalSpacingParAlways i, VerticalSpacingParSome j) ->
VerticalSpacingParAlways $ max i j
(VerticalSpacingParSome j, VerticalSpacingParAlways i) ->
VerticalSpacingParAlways $ max i j
(VerticalSpacingParSome x, VerticalSpacingParSome y) ->
VerticalSpacingParSome $ max x y) False))
(LineModeValid $ VerticalSpacing 0 VerticalSpacingParNone False)
sumVs :: [LineModeValidity VerticalSpacing] -> LineModeValidity VerticalSpacing
sumVs sps = foldl' (liftM2 go) initial sps
where
go (VerticalSpacing x1 x2 x3) (VerticalSpacing y1 y2 _) = VerticalSpacing
(x1 + y1)
(case (x2, y2) of
(x, VerticalSpacingParNone) -> x
(VerticalSpacingParNone, x) -> x
(VerticalSpacingParAlways i, VerticalSpacingParAlways j) ->
VerticalSpacingParAlways $ i+j
(VerticalSpacingParAlways i, VerticalSpacingParSome j) ->
VerticalSpacingParAlways $ i+j
(VerticalSpacingParSome i, VerticalSpacingParAlways j) ->
VerticalSpacingParAlways $ i+j
(VerticalSpacingParSome x, VerticalSpacingParSome y) ->
VerticalSpacingParSome $ x + y)
x3
singleline (LineModeValid x) = _vs_paragraph x == VerticalSpacingParNone
singleline _ = False
isPar (LineModeValid x) = _vs_parFlag x
isPar _ = False
parFlag = case sps of
[] -> True
_ -> all singleline (List.init sps) && isPar (List.last sps)
initial = LineModeValid $ VerticalSpacing 0 VerticalSpacingParNone parFlag
getMaxVS :: LineModeValidity VerticalSpacing -> LineModeValidity Int
getMaxVS = fmap $ \(VerticalSpacing x1 x2 _) -> x1 `max` case x2 of
VerticalSpacingParSome i -> i
VerticalSpacingParNone -> 0
VerticalSpacingParAlways i -> i
data SpecialCompare = Unequal | Smaller | Bigger
getSpacings
:: forall m
. (MonadMultiReader Config m, MonadMultiWriter (Seq String) m)
=> Int
-> BriDocNumbered
-> Memo.MemoT Int [VerticalSpacing] m [VerticalSpacing]
getSpacings limit bridoc = preFilterLimit <$> rec bridoc
where
-- when we do `take K . filter someCondition` on a list of spacings, we
-- need to first (also) limit the size of the input list, otherwise a
-- _large_ input with a similarly _large_ prefix not passing our filtering
-- process could lead to exponential runtime behaviour.
-- TODO: 3 is arbitrary.
preFilterLimit :: [VerticalSpacing] -> [VerticalSpacing]
preFilterLimit = take (3*limit)
memoWithKey :: Memo.MonadMemo k v m1 => k -> m1 v -> m1 v
memoWithKey k v = Memo.memo (const v) k
rec :: BriDocNumbered -> Memo.MemoT Int [VerticalSpacing] m [VerticalSpacing]
rec (brDcId, brdc) = memoWithKey brDcId $ do
config <- mAsk
let colMax = config & _conf_layout & _lconfig_cols & confUnpack
let hasOkColCount (VerticalSpacing lsp psp _) =
lsp <= colMax && case psp of
VerticalSpacingParNone -> True
VerticalSpacingParSome i -> i <= colMax
VerticalSpacingParAlways{} -> True
let specialCompare vs1 vs2 =
if ( (_vs_sameLine vs1 == _vs_sameLine vs2)
&& (_vs_parFlag vs1 == _vs_parFlag vs2)
)
then case (_vs_paragraph vs1, _vs_paragraph vs2) of
(VerticalSpacingParAlways i1, VerticalSpacingParAlways i2) ->
if i1 < i2 then Smaller else Bigger
(p1, p2) -> if p1 == p2 then Smaller else Unequal
else Unequal
let allowHangingQuasiQuotes =
config
& _conf_layout
& _lconfig_allowHangingQuasiQuotes
& confUnpack
let -- this is like List.nub, with one difference: if two elements
-- are unequal only in _vs_paragraph, with both ParAlways, we
-- treat them like equals and replace the first occurence with the
-- smallest member of this "equal group".
specialNub :: [VerticalSpacing] -> [VerticalSpacing]
specialNub [] = []
specialNub (x1 : xr) = case go x1 xr of
(r, xs') -> r : specialNub xs'
where
go y1 [] = (y1, [])
go y1 (y2 : yr) = case specialCompare y1 y2 of
Unequal -> let (r, yr') = go y1 yr in (r, y2 : yr')
Smaller -> go y1 yr
Bigger -> go y2 yr
let -- the standard function used to enforce a constant upper bound
-- on the number of elements returned for each node. Should be
-- applied whenever in a parent the combination of spacings from
-- its children might cause excess of the upper bound.
filterAndLimit :: [VerticalSpacing] -> [VerticalSpacing]
filterAndLimit = take limit
-- prune so we always consider a constant
-- amount of spacings per node of the BriDoc.
. specialNub
-- In the end we want to know if there is at least
-- one valid spacing for any alternative.
-- If there are duplicates in the list, then these
-- will either all be valid (so having more than the
-- first is pointless) or all invalid (in which
-- case having any of them is pointless).
-- Nonetheless I think the order of spacings should
-- be preserved as it provides a deterministic
-- choice for which spacings to prune (which is
-- an argument against simply using a Set).
-- I have also considered `fmap head . group` which
-- seems to work similarly well for common cases
-- and which might behave even better when it comes
-- to determinism of the algorithm. But determinism
-- should not be overrated here either - in the end
-- this is about deterministic behaviour of the
-- pruning we do that potentially results in
-- non-optimal layouts, and we'd rather take optimal
-- layouts when we can than take non-optimal layouts
-- just to be consistent with other cases where
-- we'd choose non-optimal layouts.
. filter hasOkColCount
-- throw out any spacings (i.e. children) that
-- already use more columns than available in
-- total.
. preFilterLimit
result <- case brdc of
-- BDWrapAnnKey _annKey bd -> rec bd
BDFEmpty ->
return $ [VerticalSpacing 0 VerticalSpacingParNone False]
BDFLit t ->
return $ [VerticalSpacing (Text.length t) VerticalSpacingParNone False]
BDFSeq list ->
fmap sumVs . sequence . fmap filterAndLimit <$> rec `mapM` list
BDFCols _sig list ->
fmap sumVs . sequence . fmap filterAndLimit <$> rec `mapM` list
BDFSeparator ->
return $ [VerticalSpacing 1 VerticalSpacingParNone False]
BDFAddBaseY indent bd -> do
mVs <- rec bd
return $ mVs <&> \vs -> vs
{ _vs_paragraph = case _vs_paragraph vs of
VerticalSpacingParNone -> VerticalSpacingParNone
VerticalSpacingParAlways i -> VerticalSpacingParAlways $ case indent of
BrIndentNone -> i
BrIndentRegular -> i + ( confUnpack
$ _lconfig_indentAmount
$ _conf_layout
$ config
)
BrIndentSpecial j -> i + j
VerticalSpacingParSome i -> VerticalSpacingParSome $ case indent of
BrIndentNone -> i
BrIndentRegular -> i + ( confUnpack
$ _lconfig_indentAmount
$ _conf_layout
$ config
)
BrIndentSpecial j -> i + j
}
BDFBaseYPushCur bd -> do
mVs <- rec bd
return $ mVs <&> \vs -> vs
-- We leave par as-is, even though it technically is not
-- accurate (in general).
-- the reason is that we really want to _keep_ it Just if it is
-- just so we properly communicate the is-multiline fact.
-- An alternative would be setting to (Just 0).
{ _vs_sameLine = max (_vs_sameLine vs)
(case _vs_paragraph vs of
VerticalSpacingParNone -> 0
VerticalSpacingParSome i -> i
VerticalSpacingParAlways i -> min colMax i)
, _vs_paragraph = case _vs_paragraph vs of
VerticalSpacingParNone -> VerticalSpacingParNone
VerticalSpacingParSome i -> VerticalSpacingParSome i
VerticalSpacingParAlways i -> VerticalSpacingParAlways i
}
BDFBaseYPop bd -> rec bd
BDFIndentLevelPushCur bd -> rec bd
BDFIndentLevelPop bd -> rec bd
BDFPar BrIndentNone sameLine indented -> do
mVss <- filterAndLimit <$> rec sameLine
indSps <- filterAndLimit <$> rec indented
let mVsIndSp = take limit
$ [ (x,y)
| x<-mVss
, y<-indSps
]
return $ mVsIndSp <&>
\(VerticalSpacing lsp mPsp _, indSp) ->
VerticalSpacing
lsp
(case mPsp of
VerticalSpacingParSome psp ->
VerticalSpacingParSome $ max psp $ getMaxVS indSp -- TODO
VerticalSpacingParNone -> spMakePar indSp
VerticalSpacingParAlways psp ->
VerticalSpacingParAlways $ max psp $ getMaxVS indSp)
( mPsp == VerticalSpacingParNone
&& _vs_paragraph indSp == VerticalSpacingParNone
&& _vs_parFlag indSp
)
BDFPar{} -> error "BDPar with indent in getSpacing"
BDFAlt [] -> error "empty BDAlt"
-- BDAlt (alt:_) -> rec alt
BDFAlt alts -> do
r <- rec `mapM` alts
return $ filterAndLimit =<< r
BDFForceMultiline bd -> do
mVs <- filterAndLimit <$> rec bd
return $ filter ((/=VerticalSpacingParNone) . _vs_paragraph) mVs
BDFForceSingleline bd -> do
mVs <- filterAndLimit <$> rec bd
return $ filter ((==VerticalSpacingParNone) . _vs_paragraph) mVs
BDFForwardLineMode bd -> rec bd
BDFExternal _ _ _ txt | [t] <- Text.lines txt ->
return $ [VerticalSpacing (Text.length t) VerticalSpacingParNone False]
BDFExternal{} ->
return $ [] -- yes, we just assume that we cannot properly layout
-- this.
BDFPlain t -> return
[ case Text.lines t of
[] -> VerticalSpacing 0 VerticalSpacingParNone False
[t1 ] -> VerticalSpacing
(Text.length t1)
VerticalSpacingParNone
False
(t1 : _) -> VerticalSpacing
(Text.length t1)
(VerticalSpacingParAlways 0)
True
| allowHangingQuasiQuotes
]
BDFAnnotationPrior _annKey bd -> rec bd
BDFAnnotationKW _annKey _kw bd -> rec bd
BDFAnnotationRest _annKey bd -> rec bd
BDFMoveToKWDP _annKey _kw _b bd -> rec bd
BDFLines [] -> return $ [VerticalSpacing 0 VerticalSpacingParNone False]
BDFLines ls@(_:_) -> do
-- we simply assume that lines is only used "properly", i.e. in
-- such a way that the first line can be treated "as a part of the
-- paragraph". That most importantly means that Lines should never
-- be inserted anywhere but at the start of the line. A
-- counterexample would be anything like Seq[Lit "foo", Lines].
lSpss <- map filterAndLimit <$> rec `mapM` ls
let worbled = fmap reverse
$ sequence
$ reverse
$ lSpss
sumF lSps@(lSp1:_) = VerticalSpacing (_vs_sameLine lSp1)
(spMakePar $ maxVs lSps)
False
sumF [] = error $ "should not happen. if my logic does not fail"
++ "me, this follows from not (null ls)."
return $ sumF <$> worbled
-- lSpss@(mVs:_) <- rec `mapM` ls
-- return $ case Control.Lens.transposeOf traverse lSpss of -- TODO: we currently only
-- -- consider the first alternative for the
-- -- line's spacings.
-- -- also i am not sure if always including
-- -- the first line length in the paragraph
-- -- length gives the desired results.
-- -- it is the safe path though, for now.
-- [] -> []
-- (lSps:_) -> mVs <&> \(VerticalSpacing lsp _) ->
-- VerticalSpacing lsp $ VerticalSpacingParSome $ getMaxVS $ maxVs lSps
BDFEnsureIndent indent bd -> do
mVs <- rec bd
let addInd = case indent of
BrIndentNone -> 0
BrIndentRegular -> confUnpack
$ _lconfig_indentAmount
$ _conf_layout
$ config
BrIndentSpecial i -> i
return $ mVs <&> \(VerticalSpacing lsp psp parFlag) ->
VerticalSpacing (lsp + addInd) psp parFlag
BDFNonBottomSpacing b bd -> do
-- TODO: the `b` flag is an ugly hack, but I was not able to make
-- all tests work without it. It should be possible to have
-- `spMakePar` map VSPAlways{} to VSPSome x1, which fixes this
-- problem but breaks certain other cases.
mVs <- rec bd
return $ if null mVs
then [VerticalSpacing
0
(if b then VerticalSpacingParSome 0
else VerticalSpacingParAlways colMax
)
False
]
else mVs <&> \vs -> vs
{ _vs_sameLine = min colMax (_vs_sameLine vs)
, _vs_paragraph = case _vs_paragraph vs of
VerticalSpacingParNone -> VerticalSpacingParNone
VerticalSpacingParAlways i
| b -> VerticalSpacingParSome 0
| otherwise -> VerticalSpacingParAlways i
VerticalSpacingParSome i
| b -> VerticalSpacingParSome 0
| otherwise -> VerticalSpacingParAlways i
}
-- the version below is an alternative idea: fold the input
-- spacings into a single spacing. This was hoped to improve in
-- certain cases where non-bottom alternatives took up "too much
-- explored search space"; the downside is that it also cuts
-- the search-space short in other cases where it is not necessary,
-- leading to unnecessary new-lines. Disabled for now. A better
-- solution would require conditionally folding the search-space
-- only in appropriate locations (i.e. a new BriDoc node type
-- for this purpose, perhaps "BDFNonBottomSpacing1").
-- else
-- [ Foldable.foldl1
-- (\(VerticalSpacing x1 x2 _) (VerticalSpacing y1 y2 _) ->
-- VerticalSpacing
-- (min x1 y1)
-- (case (x2, y2) of
-- (x, VerticalSpacingParNone) -> x
-- (VerticalSpacingParNone, x) -> x
-- (VerticalSpacingParAlways i, VerticalSpacingParAlways j) ->
-- VerticalSpacingParAlways $ min i j
-- (VerticalSpacingParAlways i, VerticalSpacingParSome j) ->
-- VerticalSpacingParAlways $ min i j
-- (VerticalSpacingParSome i, VerticalSpacingParAlways j) ->
-- VerticalSpacingParAlways $ min i j
-- (VerticalSpacingParSome x, VerticalSpacingParSome y) ->
-- VerticalSpacingParSome $ min x y)
-- False)
-- mVs
-- ]
BDFSetParSpacing bd -> do
mVs <- rec bd
return $ mVs <&> \vs -> vs { _vs_parFlag = True }
BDFForceParSpacing bd -> do
mVs <- preFilterLimit <$> rec bd
return $ [ vs | vs <- mVs, _vs_parFlag vs || _vs_paragraph vs == VerticalSpacingParNone ]
BDFDebug s bd -> do
r <- rec bd
tellDebugMess $ "getSpacings: BDFDebug " ++ show s ++ " (node-id=" ++ show brDcId ++ "): vs=" ++ show (take 9 r)
return r
#if INSERTTRACESGETSPACING
case brdc of
BDFAnnotationPrior{} -> return ()
BDFAnnotationRest{} -> return ()
_ -> mTell $ Seq.fromList ["getSpacings: visiting: "
++ show (toConstr $ brdc) -- (briDocToDoc $ unwrapBriDocNumbered (0, brdc))
, " -> "
++ show (take 9 result)
]
#endif
return result
maxVs :: [VerticalSpacing] -> VerticalSpacing
maxVs = foldl'
(\(VerticalSpacing x1 x2 _) (VerticalSpacing y1 y2 _) ->
VerticalSpacing
(max x1 y1)
(case (x2, y2) of
(x, VerticalSpacingParNone) -> x
(VerticalSpacingParNone, x) -> x
(VerticalSpacingParAlways i, VerticalSpacingParAlways j) ->
VerticalSpacingParAlways $ max i j
(VerticalSpacingParAlways i, VerticalSpacingParSome j) ->
VerticalSpacingParAlways $ max i j
(VerticalSpacingParSome i, VerticalSpacingParAlways j) ->
VerticalSpacingParAlways $ max i j
(VerticalSpacingParSome x, VerticalSpacingParSome y) ->
VerticalSpacingParSome $ max x y)
False)
(VerticalSpacing 0 VerticalSpacingParNone False)
sumVs :: [VerticalSpacing] -> VerticalSpacing
sumVs sps = foldl' go initial sps
where
go (VerticalSpacing x1 x2 x3) (VerticalSpacing y1 y2 _) = VerticalSpacing
(x1 + y1)
(case (x2, y2) of
(x, VerticalSpacingParNone) -> x
(VerticalSpacingParNone, x) -> x
(VerticalSpacingParAlways i, VerticalSpacingParAlways j) ->
VerticalSpacingParAlways $ i+j
(VerticalSpacingParAlways i, VerticalSpacingParSome j) ->
VerticalSpacingParAlways $ i+j
(VerticalSpacingParSome i, VerticalSpacingParAlways j) ->
VerticalSpacingParAlways $ i+j
(VerticalSpacingParSome x, VerticalSpacingParSome y) -> VerticalSpacingParSome $ x + y)
x3
singleline x = _vs_paragraph x == VerticalSpacingParNone
isPar x = _vs_parFlag x
parFlag = case sps of
[] -> True
_ -> all singleline (List.init sps) && isPar (List.last sps)
initial = VerticalSpacing 0 VerticalSpacingParNone parFlag
getMaxVS :: VerticalSpacing -> Int
getMaxVS (VerticalSpacing x1 x2 _) = x1 `max` case x2 of
VerticalSpacingParSome i -> i
VerticalSpacingParNone -> 0
VerticalSpacingParAlways i -> i
spMakePar :: VerticalSpacing -> VerticalSpacingPar
spMakePar (VerticalSpacing x1 x2 _) = case x2 of
VerticalSpacingParSome i -> VerticalSpacingParSome $ x1 `max` i
VerticalSpacingParNone -> VerticalSpacingParSome $ x1
VerticalSpacingParAlways i -> VerticalSpacingParAlways $ x1 `max` i
fixIndentationForMultiple
:: (MonadMultiReader (CConfig Identity) m) => AltCurPos -> BrIndent -> m Int
fixIndentationForMultiple acp indent = do
indAmount <- mAsk <&> _conf_layout .> _lconfig_indentAmount .> confUnpack
let indAddRaw = case indent of
BrIndentNone -> 0
BrIndentRegular -> indAmount
BrIndentSpecial i -> i
-- for IndentPolicyMultiple, we restrict the amount of added
-- indentation in such a manner that we end up on a multiple of the
-- base indentation.
indPolicy <- mAsk <&> _conf_layout .> _lconfig_indentPolicy .> confUnpack
pure $ if indPolicy == IndentPolicyMultiple
then
let indAddMultiple1 =
indAddRaw - ((_acp_indent acp + indAddRaw) `mod` indAmount)
indAddMultiple2 = if indAddMultiple1 <= 0
then indAddMultiple1 + indAmount
else indAddMultiple1
in indAddMultiple2
else indAddRaw