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author | Jesse Rosenthal <jrosenthal@jhu.edu> | 2014-08-16 10:22:55 -0400 |
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committer | Jesse Rosenthal <jrosenthal@jhu.edu> | 2014-08-16 10:22:55 -0400 |
commit | 0ff9ec2f4e35bf3e99e2e71837d01e9f2e107798 (patch) | |
tree | a5bdbaa5929226337b5be6dde4f8030b2370ab8c /src/Text/Pandoc/Readers/Docx/Reducible.hs | |
parent | 2b6e8f4c83e12d5534d7c21a0882a9f4c1e3cb1d (diff) | |
download | pandoc-0ff9ec2f4e35bf3e99e2e71837d01e9f2e107798.tar.gz |
Rewrite Docx.hs and Reducible to use Builder.
The big news here is a rewrite of Docx to use the builder
functions. As opposed to previous attempts, we now see a significant
speedup -- times are cut in half (or more) in a few informal tests.
Reducible has also been rewritten. It can doubtless be simplified and
clarified further. We can consider this, at the moment, a reference for
correct behavior.
Diffstat (limited to 'src/Text/Pandoc/Readers/Docx/Reducible.hs')
-rw-r--r-- | src/Text/Pandoc/Readers/Docx/Reducible.hs | 364 |
1 files changed, 175 insertions, 189 deletions
diff --git a/src/Text/Pandoc/Readers/Docx/Reducible.hs b/src/Text/Pandoc/Readers/Docx/Reducible.hs index 80a0cee17..8269ca88d 100644 --- a/src/Text/Pandoc/Readers/Docx/Reducible.hs +++ b/src/Text/Pandoc/Readers/Docx/Reducible.hs @@ -1,196 +1,182 @@ -{-# LANGUAGE OverloadedStrings, PatternGuards #-} - -{- -Copyright (C) 2014 Jesse Rosenthal <jrosenthal@jhu.edu> - -This program is free software; you can redistribute it and/or modify -it under the terms of the GNU General Public License as published by -the Free Software Foundation; either version 2 of the License, or -(at your option) any later version. - -This program is distributed in the hope that it will be useful, -but WITHOUT ANY WARRANTY; without even the implied warranty of -MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the -GNU General Public License for more details. - -You should have received a copy of the GNU General Public License -along with this program; if not, write to the Free Software -Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA --} - -{- | - Module : Text.Pandoc.Readers.Docx.Reducible - Copyright : Copyright (C) 2014 Jesse Rosenthal - License : GNU GPL, version 2 or above - - Maintainer : Jesse Rosenthal <jrosenthal@jhu.edu> - Stability : alpha - Portability : portable - -Typeclass for combining adjacent blocks and inlines correctly. --} - - -module Text.Pandoc.Readers.Docx.Reducible ((<++>), - (<+++>), - Reducible, - Container(..), - container, - innards, - reduceList, - reduceListB, - concatR, - rebuild) - where +{-# LANGUAGE TypeSynonymInstances, FlexibleInstances, + PatternGuards #-} -import Text.Pandoc.Builder -import Data.List ((\\), intersect) +module Text.Pandoc.Readers.Docx.Reducible ( concatReduce + , (<+>) + ) + where -data Container a = Container ([a] -> a) | NullContainer -instance (Eq a) => Eq (Container a) where - (Container x) == (Container y) = ((x []) == (y [])) - NullContainer == NullContainer = True +import Text.Pandoc.Builder +import Data.Monoid +import Data.List +import Data.Sequence (ViewR(..), ViewL(..), viewl, viewr) +import qualified Data.Sequence as Seq (null) + +data Modifier a = Modifier (a -> a) + | AttrModifier (Attr -> a -> a) Attr + | NullModifier + +class (Eq a) => Modifiable a where + modifier :: a -> Modifier a + innards :: a -> a + getL :: a -> (a, a) + getR :: a -> (a, a) + spaceOut :: a -> (a, a, a) + +spaceOutL :: (Monoid a, Modifiable a) => a -> (a, a) +spaceOutL ms = (l, stack fs (m' <> r)) + where (l, m, r) = spaceOut ms + (fs, m') = unstack m + +spaceOutR :: (Monoid a, Modifiable a) => a -> (a, a) +spaceOutR ms = (stack fs (l <> m'), r) + where (l, m, r) = spaceOut ms + (fs, m') = unstack m + +instance (Monoid a, Show a) => Show (Modifier a) where + show (Modifier f) = show $ f mempty + show (AttrModifier f attr) = show $ f attr mempty + show (NullModifier) = "NullModifier" + +instance (Monoid a, Eq a) => Eq (Modifier a) where + (Modifier f) == (Modifier g) = (f mempty == g mempty) + (AttrModifier f attr) == (AttrModifier g attr') = (f attr mempty == g attr' mempty) + (NullModifier) == (NullModifier) = True _ == _ = False -instance (Show a) => Show (Container a) where - show (Container x) = "Container {" ++ - (reverse $ drop 3 $ reverse $ show $ x []) ++ - "}" - show (NullContainer) = "NullContainer" - -class Reducible a where - (<++>) :: a -> a -> [a] - container :: a -> Container a - innards :: a -> [a] - isSpace :: a -> Bool - -(<+++>) :: (Reducible a) => Many a -> Many a -> Many a -mr <+++> ms = fromList $ reduceList $ toList mr ++ toList ms - -reduceListB :: (Reducible a) => Many a -> Many a -reduceListB = fromList . reduceList . toList - -reduceList' :: (Reducible a) => [a] -> [a] -> [a] -reduceList' acc [] = acc -reduceList' [] (x:xs) = reduceList' [x] xs -reduceList' as (x:xs) = reduceList' (init as ++ (last as <++> x) ) xs - -reduceList :: (Reducible a) => [a] -> [a] -reduceList = reduceList' [] - -concatR :: (Reducible a) => [a] -> [a] -> [a] -concatR [] [] = [] -concatR [] ss = ss -concatR rs [] = rs -concatR rs ss = let (x:xs) = reverse rs - (y:ys) = ss - in - reverse xs ++ ( x <++> y ) ++ ys - -combineReducibles :: (Reducible a, Eq a) => a -> a -> [a] -combineReducibles r s = - let (conts, rs) = topLevelContainers r - (conts', ss) = topLevelContainers s - shared = conts `intersect` conts' - remaining = conts \\ shared - remaining' = conts' \\ shared +instance Modifiable Inlines where + modifier ils = case viewl (unMany ils) of + (x :< xs) | Seq.null xs -> case x of + (Emph _) -> Modifier emph + (Strong _) -> Modifier strong + (SmallCaps _) -> Modifier smallcaps + (Strikeout _) -> Modifier strikeout + (Superscript _) -> Modifier superscript + (Subscript _) -> Modifier subscript + (Span attr _) -> AttrModifier spanWith attr + _ -> NullModifier + _ -> NullModifier + + innards ils = case viewl (unMany ils) of + (x :< xs) | Seq.null xs -> case x of + (Emph lst) -> fromList lst + (Strong lst) -> fromList lst + (SmallCaps lst) -> fromList lst + (Strikeout lst) -> fromList lst + (Superscript lst) -> fromList lst + (Subscript lst) -> fromList lst + (Span _ lst) -> fromList lst + _ -> ils + _ -> ils + + getL ils = case viewl $ unMany ils of + (s :< sq) -> (singleton s, Many sq) + _ -> (mempty, ils) + + getR ils = case viewr $ unMany ils of + (sq :> s) -> (Many sq, singleton s) + _ -> (ils, mempty) + + spaceOut ils = + let (fs, ils') = unstack ils + contents = unMany ils' + left = case viewl contents of + (Space :< _) -> space + _ -> mempty + right = case viewr contents of + (_ :> Space) -> space + _ -> mempty in + (left, (stack fs $ trimInlines .Many $ contents), right) + +instance Modifiable Blocks where + modifier blks = case viewl (unMany blks) of + (x :< xs) | Seq.null xs -> case x of + (BlockQuote _) -> Modifier blockQuote + -- (Div attr _) -> AttrModifier divWith attr + _ -> NullModifier + _ -> NullModifier + + innards blks = case viewl (unMany blks) of + (x :< xs) | Seq.null xs -> case x of + (BlockQuote lst) -> fromList lst + -- (Div attr lst) -> fromList lst + _ -> blks + _ -> blks + + spaceOut blks = (mempty, blks, mempty) + + getL ils = case viewl $ unMany ils of + (s :< sq) -> (singleton s, Many sq) + _ -> (mempty, ils) + + getR ils = case viewr $ unMany ils of + (sq :> s) -> (Many sq, singleton s) + _ -> (ils, mempty) + + +unstack :: (Modifiable a) => a -> ([Modifier a], a) +unstack ms = case modifier ms of + NullModifier -> ([], ms) + _ -> (f : fs, ms') where + f = modifier ms + (fs, ms') = unstack $ innards ms + +stack :: (Monoid a, Modifiable a) => [Modifier a] -> a -> a +stack [] ms = ms +stack (NullModifier : fs) ms = stack fs ms +stack ((Modifier f) : fs) ms = + if isEmpty ms + then stack fs ms + else f $ stack fs ms +stack ((AttrModifier f attr) : fs) ms = f attr $ stack fs ms + +isEmpty :: (Monoid a, Eq a) => a -> Bool +isEmpty x = x == mempty + + +combine :: (Monoid a, Modifiable a, Eq a) => a -> a -> a +combine x y = + let (xs', x') = getR x + (y', ys') = getL y + in + xs' <> (combineSingleton x' y') <> ys' + +isAttrModifier :: Modifier a -> Bool +isAttrModifier (AttrModifier _ _) = True +isAttrModifier _ = False + +combineSingleton :: (Monoid a, Modifiable a, Eq a) => a -> a -> a +combineSingleton x y = + let (xfs, xs) = unstack x + (yfs, ys) = unstack y + shared = xfs `intersect` yfs + x_remaining = xfs \\ shared + y_remaining = yfs \\ shared + x_rem_attr = filter isAttrModifier x_remaining + y_rem_attr = filter isAttrModifier y_remaining in case null shared of - True | (x : xs) <- reverse rs - , isSpace x -> case xs of - [] -> [x, s] - _ -> rebuild conts (reverse xs) ++ [x, s] - | (x : xs) <- ss - , isSpace x -> case xs of - [] -> [r, x] - _ -> [r, x] ++ rebuild conts' (xs) - True -> [r,s] - False -> rebuild - shared $ - reduceList $ - (rebuild remaining rs) ++ (rebuild remaining' ss) - -instance Reducible Inline where - s1@(Span (id1, classes1, kvs1) ils1) <++> s2@(Span (id2, classes2, kvs2) ils2) = - let classes' = classes1 `intersect` classes2 - kvs' = kvs1 `intersect` kvs2 - classes1' = classes1 \\ classes' - kvs1' = kvs1 \\ kvs' - classes2' = classes2 \\ classes' - kvs2' = kvs2 \\ kvs' - in - case null classes' && null kvs' of - True -> [s1,s2] - False -> let attr' = ("", classes', kvs') - attr1' = (id1, classes1', kvs1') - attr2' = (id2, classes2', kvs2') - s1' = case null classes1' && null kvs1' of - True -> ils1 - False -> [Span attr1' ils1] - s2' = case null classes2' && null kvs2' of - True -> ils2 - False -> [Span attr2' ils2] - in - [Span attr' $ reduceList $ s1' ++ s2'] - (Str x) <++> (Str y) = [Str (x++y)] - il <++> il' = combineReducibles il il' - - container (Emph _) = Container Emph - container (Strong _) = Container Strong - container (SmallCaps _) = Container SmallCaps - container (Strikeout _) = Container Strikeout - container (Subscript _) = Container Subscript - container (Superscript _) = Container Superscript - container (Quoted qt _) = Container $ Quoted qt - container (Cite cs _) = Container $ Cite cs - container (Span attr _) = Container $ Span attr - container _ = NullContainer - - innards (Emph ils) = ils - innards (SmallCaps ils) = ils - innards (Strong ils) = ils - innards (Strikeout ils) = ils - innards (Subscript ils) = ils - innards (Superscript ils) = ils - innards (Quoted _ ils) = ils - innards (Cite _ ils) = ils - innards (Span _ ils) = ils - innards _ = [] - - isSpace Space = True - isSpace _ = False - -instance Reducible Block where - (Div (ident, classes, kvs) blks) <++> blk | "list-item" `elem` classes = - [Div (ident, classes, kvs) (reduceList blks), blk] - - blk <++> blk' = combineReducibles blk blk' - - container (BlockQuote _) = Container BlockQuote - container (Div attr _) = Container $ Div attr - container _ = NullContainer - - innards (BlockQuote bs) = bs - innards (Div _ bs) = bs - innards _ = [] - - isSpace _ = False - - -topLevelContainers' :: (Reducible a) => [a] -> ([Container a], [a]) -topLevelContainers' (r : []) = case container r of - NullContainer -> ([], [r]) - _ -> - let (conts, inns) = topLevelContainers' (innards r) - in - ((container r) : conts, inns) -topLevelContainers' rs = ([], rs) - -topLevelContainers :: (Reducible a) => a -> ([Container a], [a]) -topLevelContainers il = topLevelContainers' [il] - -rebuild :: [Container a] -> [a] -> [a] -rebuild [] xs = xs -rebuild ((Container f) : cs) xs = rebuild cs $ [f xs] -rebuild (NullContainer : cs) xs = rebuild cs $ xs + True | isEmpty xs && isEmpty ys -> + stack (x_rem_attr ++ y_rem_attr) mempty + | isEmpty xs -> + let (sp, y') = spaceOutL y in + (stack x_rem_attr mempty) <> sp <> y' + | isEmpty ys -> + let (x', sp) = spaceOutR x in + x' <> sp <> (stack y_rem_attr mempty) + | otherwise -> + let (x', xsp) = spaceOutR x + (ysp, y') = spaceOutL y + in + x' <> xsp <> ysp <> y' + False -> stack shared $ + combine + (stack x_remaining xs) + (stack y_remaining ys) + +(<+>) :: (Monoid a, Modifiable a, Eq a) => a -> a -> a +x <+> y = combine x y + +concatReduce :: (Monoid a, Modifiable a) => [a] -> a +concatReduce xs = foldl combine mempty xs |