brittany-0.14.0.2: source/library/Language/Haskell/Brittany/Internal/Transformations/Floating.hs
{-# LANGUAGE LambdaCase #-}
{-# LANGUAGE NoImplicitPrelude #-}
module Language.Haskell.Brittany.Internal.Transformations.Floating where
import qualified Data.Generics.Uniplate.Direct as Uniplate
import qualified GHC.OldList as List
import Language.Haskell.Brittany.Internal.Prelude
import Language.Haskell.Brittany.Internal.PreludeUtils
import Language.Haskell.Brittany.Internal.Types
import Language.Haskell.Brittany.Internal.Utils
-- note that this is not total, and cannot be with that exact signature.
mergeIndents :: BrIndent -> BrIndent -> BrIndent
mergeIndents BrIndentNone x = x
mergeIndents x BrIndentNone = x
mergeIndents (BrIndentSpecial i) (BrIndentSpecial j) =
BrIndentSpecial (max i j)
mergeIndents _ _ = error "mergeIndents"
transformSimplifyFloating :: BriDoc -> BriDoc
transformSimplifyFloating = stepBO .> stepFull
-- note that semantically, stepFull is completely sufficient.
-- but the bottom-up switch-to-top-down-on-match transformation has much
-- better complexity.
-- UPDATE: by now, stepBO does more than stepFull; for semantic equivalence
-- the push/pop cases would need to be copied over
where
descendPrior = transformDownMay $ \case
-- prior floating in
BDAnnotationPrior annKey1 (BDPar ind line indented) ->
Just $ BDPar ind (BDAnnotationPrior annKey1 line) indented
BDAnnotationPrior annKey1 (BDSeq (l : lr)) ->
Just $ BDSeq (BDAnnotationPrior annKey1 l : lr)
BDAnnotationPrior annKey1 (BDLines (l : lr)) ->
Just $ BDLines (BDAnnotationPrior annKey1 l : lr)
BDAnnotationPrior annKey1 (BDCols sig (l : lr)) ->
Just $ BDCols sig (BDAnnotationPrior annKey1 l : lr)
BDAnnotationPrior annKey1 (BDAddBaseY indent x) ->
Just $ BDAddBaseY indent $ BDAnnotationPrior annKey1 x
BDAnnotationPrior annKey1 (BDDebug s x) ->
Just $ BDDebug s $ BDAnnotationPrior annKey1 x
_ -> Nothing
descendRest = transformDownMay $ \case
-- post floating in
BDAnnotationRest annKey1 (BDPar ind line indented) ->
Just $ BDPar ind line $ BDAnnotationRest annKey1 indented
BDAnnotationRest annKey1 (BDSeq list) ->
Just
$ BDSeq
$ List.init list
++ [BDAnnotationRest annKey1 $ List.last list]
BDAnnotationRest annKey1 (BDLines list) ->
Just
$ BDLines
$ List.init list
++ [BDAnnotationRest annKey1 $ List.last list]
BDAnnotationRest annKey1 (BDCols sig cols) ->
Just
$ BDCols sig
$ List.init cols
++ [BDAnnotationRest annKey1 $ List.last cols]
BDAnnotationRest annKey1 (BDAddBaseY indent x) ->
Just $ BDAddBaseY indent $ BDAnnotationRest annKey1 x
BDAnnotationRest annKey1 (BDDebug s x) ->
Just $ BDDebug s $ BDAnnotationRest annKey1 x
_ -> Nothing
descendKW = transformDownMay $ \case
-- post floating in
BDAnnotationKW annKey1 kw (BDPar ind line indented) ->
Just $ BDPar ind line $ BDAnnotationKW annKey1 kw indented
BDAnnotationKW annKey1 kw (BDSeq list) ->
Just
$ BDSeq
$ List.init list
++ [BDAnnotationKW annKey1 kw $ List.last list]
BDAnnotationKW annKey1 kw (BDLines list) ->
Just
$ BDLines
$ List.init list
++ [BDAnnotationKW annKey1 kw $ List.last list]
BDAnnotationKW annKey1 kw (BDCols sig cols) ->
Just
$ BDCols sig
$ List.init cols
++ [BDAnnotationKW annKey1 kw $ List.last cols]
BDAnnotationKW annKey1 kw (BDAddBaseY indent x) ->
Just $ BDAddBaseY indent $ BDAnnotationKW annKey1 kw x
BDAnnotationKW annKey1 kw (BDDebug s x) ->
Just $ BDDebug s $ BDAnnotationKW annKey1 kw x
_ -> Nothing
descendBYPush = transformDownMay $ \case
BDBaseYPushCur (BDCols sig cols@(_ : _)) ->
Just $ BDCols sig (BDBaseYPushCur (List.head cols) : List.tail cols)
BDBaseYPushCur (BDDebug s x) -> Just $ BDDebug s (BDBaseYPushCur x)
_ -> Nothing
descendBYPop = transformDownMay $ \case
BDBaseYPop (BDCols sig cols@(_ : _)) ->
Just $ BDCols sig (List.init cols ++ [BDBaseYPop (List.last cols)])
BDBaseYPop (BDDebug s x) -> Just $ BDDebug s (BDBaseYPop x)
_ -> Nothing
descendILPush = transformDownMay $ \case
BDIndentLevelPushCur (BDCols sig cols@(_ : _)) ->
Just $ BDCols sig (BDIndentLevelPushCur (List.head cols) : List.tail cols)
BDIndentLevelPushCur (BDDebug s x) ->
Just $ BDDebug s (BDIndentLevelPushCur x)
_ -> Nothing
descendILPop = transformDownMay $ \case
BDIndentLevelPop (BDCols sig cols@(_ : _)) ->
Just $ BDCols sig (List.init cols ++ [BDIndentLevelPop (List.last cols)])
BDIndentLevelPop (BDDebug s x) -> Just $ BDDebug s (BDIndentLevelPop x)
_ -> Nothing
descendAddB = transformDownMay $ \case
BDAddBaseY BrIndentNone x -> Just x
-- AddIndent floats into Lines.
BDAddBaseY indent (BDLines lines) ->
Just $ BDLines $ BDAddBaseY indent <$> lines
-- AddIndent floats into last column
BDAddBaseY indent (BDCols sig cols) ->
Just $ BDCols sig $ List.init cols ++ [BDAddBaseY indent $ List.last cols]
-- merge AddIndent and Par
BDAddBaseY ind1 (BDPar ind2 line indented) ->
Just $ BDPar (mergeIndents ind1 ind2) line indented
BDAddBaseY ind (BDAnnotationPrior annKey1 x) ->
Just $ BDAnnotationPrior annKey1 (BDAddBaseY ind x)
BDAddBaseY ind (BDAnnotationRest annKey1 x) ->
Just $ BDAnnotationRest annKey1 (BDAddBaseY ind x)
BDAddBaseY ind (BDAnnotationKW annKey1 kw x) ->
Just $ BDAnnotationKW annKey1 kw (BDAddBaseY ind x)
BDAddBaseY ind (BDSeq list) ->
Just $ BDSeq $ List.init list ++ [BDAddBaseY ind (List.last list)]
BDAddBaseY _ lit@BDLit{} -> Just $ lit
BDAddBaseY ind (BDBaseYPushCur x) ->
Just $ BDBaseYPushCur (BDAddBaseY ind x)
BDAddBaseY ind (BDBaseYPop x) -> Just $ BDBaseYPop (BDAddBaseY ind x)
BDAddBaseY ind (BDDebug s x) -> Just $ BDDebug s (BDAddBaseY ind x)
BDAddBaseY ind (BDIndentLevelPop x) ->
Just $ BDIndentLevelPop (BDAddBaseY ind x)
BDAddBaseY ind (BDIndentLevelPushCur x) ->
Just $ BDIndentLevelPushCur (BDAddBaseY ind x)
BDAddBaseY ind (BDEnsureIndent ind2 x) ->
Just $ BDEnsureIndent (mergeIndents ind ind2) x
_ -> Nothing
stepBO :: BriDoc -> BriDoc
stepBO = -- traceFunctionWith "stepBO" (show . briDocToDocWithAnns) (show . briDocToDocWithAnns) $
transformUp f
where
f = \case
x@BDAnnotationPrior{} -> descendPrior x
x@BDAnnotationKW{} -> descendKW x
x@BDAnnotationRest{} -> descendRest x
x@BDAddBaseY{} -> descendAddB x
x@BDBaseYPushCur{} -> descendBYPush x
x@BDBaseYPop{} -> descendBYPop x
x@BDIndentLevelPushCur{} -> descendILPush x
x@BDIndentLevelPop{} -> descendILPop x
x -> x
stepFull = -- traceFunctionWith "stepFull" (show . briDocToDocWithAnns) (show . briDocToDocWithAnns) $
Uniplate.rewrite $ \case
BDAddBaseY BrIndentNone x -> Just $ x
-- AddIndent floats into Lines.
BDAddBaseY indent (BDLines lines) ->
Just $ BDLines $ BDAddBaseY indent <$> lines
-- AddIndent floats into last column
BDAddBaseY indent (BDCols sig cols) ->
Just $ BDCols sig $ List.init cols ++ [BDAddBaseY indent $ List.last cols]
BDAddBaseY ind (BDSeq list) ->
Just $ BDSeq $ List.init list ++ [BDAddBaseY ind (List.last list)]
-- merge AddIndent and Par
BDAddBaseY ind1 (BDPar ind2 line indented) ->
Just $ BDPar (mergeIndents ind1 ind2) line indented
BDAddBaseY _ lit@BDLit{} -> Just $ lit
BDAddBaseY ind (BDBaseYPushCur x) ->
Just $ BDBaseYPushCur (BDAddBaseY ind x)
BDAddBaseY ind (BDBaseYPop x) -> Just $ BDBaseYPop (BDAddBaseY ind x)
-- prior floating in
BDAnnotationPrior annKey1 (BDPar ind line indented) ->
Just $ BDPar ind (BDAnnotationPrior annKey1 line) indented
BDAnnotationPrior annKey1 (BDSeq (l : lr)) ->
Just $ BDSeq ((BDAnnotationPrior annKey1 l) : lr)
BDAnnotationPrior annKey1 (BDLines (l : lr)) ->
Just $ BDLines ((BDAnnotationPrior annKey1 l) : lr)
BDAnnotationPrior annKey1 (BDCols sig (l : lr)) ->
Just $ BDCols sig ((BDAnnotationPrior annKey1 l) : lr)
-- EnsureIndent float-in
-- BDEnsureIndent indent (BDCols sig (col:colr)) ->
-- Just $ BDCols sig (BDEnsureIndent indent col : (BDAddBaseY indent <$> colr))
-- not sure if the following rule is necessary; tests currently are
-- unaffected.
-- BDEnsureIndent indent (BDLines lines) ->
-- Just $ BDLines $ BDEnsureIndent indent <$> lines
-- post floating in
BDAnnotationRest annKey1 (BDPar ind line indented) ->
Just $ BDPar ind line $ BDAnnotationRest annKey1 indented
BDAnnotationRest annKey1 (BDSeq list) ->
Just
$ BDSeq
$ List.init list
++ [BDAnnotationRest annKey1 $ List.last list]
BDAnnotationRest annKey1 (BDLines list) ->
Just
$ BDLines
$ List.init list
++ [BDAnnotationRest annKey1 $ List.last list]
BDAnnotationRest annKey1 (BDCols sig cols) ->
Just
$ BDCols sig
$ List.init cols
++ [BDAnnotationRest annKey1 $ List.last cols]
_ -> Nothing