diff --git a/CHANGELOG b/CHANGELOG --- a/CHANGELOG +++ b/CHANGELOG @@ -1,3 +1,11 @@ +0.9 +--- + +- insertChar and insertMany now only insert printable characters and + newlines (subject to text zipper line limits) +- The GenericTextZipper class now requires a new method, + toList :: a -> [Char] + 0.8.3 ----- diff --git a/src/Data/Text/Zipper.hs b/src/Data/Text/Zipper.hs --- a/src/Data/Text/Zipper.hs +++ b/src/Data/Text/Zipper.hs @@ -46,6 +46,7 @@ import Control.Applicative ((<$>)) import Control.DeepSeq +import Data.Char (isPrint) import Data.Monoid import qualified Data.Text as T import qualified Data.Vector as V @@ -64,6 +65,7 @@ , init_ :: a -> a , null_ :: a -> Bool , lines_ :: a -> [a] + , toList_ :: a -> [Char] , lineLimit :: Maybe Int } @@ -118,19 +120,21 @@ -- ^'null'. -> (a -> [a]) -- ^'lines'. + -> (a -> [Char]) + -- ^'toList'. -> [a] -- ^The initial lines of text. -> Maybe Int -- ^Limit to this many lines of text ('Nothing' means no limit). -> TextZipper a -mkZipper fromCh drp tk lngth lst int nl linesFunc ls lmt = +mkZipper fromCh drp tk lngth lst int nl linesFunc toListF ls lmt = let limitedLs = case lmt of Nothing -> ls Just n -> take n ls (first, rest) = if null limitedLs then (mempty, mempty) else (head limitedLs, tail limitedLs) - in TZ mempty first [] rest fromCh drp tk lngth lst int nl linesFunc lmt + in TZ mempty first [] rest fromCh drp tk lngth lst int nl linesFunc toListF lmt -- |Get the text contents of the zipper. getText :: (Monoid a) => TextZipper a -> [a] @@ -184,36 +188,37 @@ currentLine :: (Monoid a) => TextZipper a -> a currentLine tz = (toLeft tz) `mappend` (toRight tz) --- |Insert a character at the current cursor position. Move the --- cursor one position to the right. +-- |Insert a character at the current cursor position. +-- +-- If the character is a newline, break the current line. +-- +-- If the character is non-printable, ignore it. +-- +-- Otherwise insert the character and move the cursor one position to +-- the right. insertChar :: (Monoid a) => Char -> TextZipper a -> TextZipper a -insertChar '\n' tz = breakLine tz -insertChar ch tz = tz { toLeft = toLeft tz `mappend` (fromChar tz ch) } +insertChar ch tz = maybe tz id $ insertChar_ ch tz +insertChar_ :: (Monoid a) => Char -> TextZipper a -> Maybe (TextZipper a) +insertChar_ ch tz + | ch == '\n' = breakLine_ tz + | isPrint ch = Just $ tz { toLeft = toLeft tz `mappend` (fromChar tz ch) } + | otherwise = Nothing + -- |Insert many characters at the current cursor position. Move the --- cursor one position to the end of the inserted text. +-- cursor to the end of the inserted text. insertMany :: (Monoid a) => a -> TextZipper a -> TextZipper a -insertMany cs tz = - let ls = lines_ tz cs - go [] z = z - go (a:as) z = let maybeBreak = if null as then id else breakLine - in go as $ maybeBreak $ z { toLeft = toLeft z `mappend` a } - in case lineLimit tz of - Nothing -> - let toInsert = ls - in go toInsert tz - Just limit -> - -- How many more lines can we add without violating the - -- limit? - let toInsert = take remainingLines ls - remainingLines = max 0 (limit - totalLines) - totalLines = length (above tz) + - length (below tz) - in go toInsert tz +insertMany str tz = + let go [] z = z + go (c:cs) z = maybe z (go cs) $ insertChar_ c z + in go (toList_ tz str) tz -- |Insert a line break at the current cursor position. breakLine :: (Monoid a) => TextZipper a -> TextZipper a -breakLine tz = +breakLine tz = maybe tz id $ breakLine_ tz + +breakLine_ :: (Monoid a) => TextZipper a -> Maybe (TextZipper a) +breakLine_ tz = -- Plus two because we count the current line and the line we are -- about to create; if that number of lines exceeds the limit, -- ignore this operation. @@ -222,9 +227,10 @@ } in case lineLimit tz of Just lim -> if length (above tz) + length (below tz) + 2 > lim - then tz - else modified - Nothing -> modified + then Nothing + else Just modified + Nothing -> Just modified + -- |Move the cursor to the end of the current line. gotoEOL :: (Monoid a) => TextZipper a -> TextZipper a gotoEOL tz = tz { toLeft = currentLine tz @@ -393,12 +399,12 @@ -- |Construct a zipper from list values. stringZipper :: [String] -> Maybe Int -> TextZipper String stringZipper = - mkZipper (:[]) drop take length last init null lines + mkZipper (:[]) drop take length last init null lines id -- |Construct a zipper from vectors of characters. vectorZipper :: [V.Vector Char] -> Maybe Int -> TextZipper (V.Vector Char) vectorZipper = - mkZipper V.singleton V.drop V.take V.length V.last V.init V.null V.vecLines + mkZipper V.singleton V.drop V.take V.length V.last V.init V.null V.vecLines V.toList -- |Empty a zipper. clearZipper :: (Monoid a) => TextZipper a -> TextZipper a @@ -412,4 +418,4 @@ -- |Construct a zipper from 'T.Text' values. textZipper :: [T.Text] -> Maybe Int -> TextZipper T.Text textZipper = - mkZipper T.singleton T.drop T.take T.length T.last T.init T.null T.lines + mkZipper T.singleton T.drop T.take T.length T.last T.init T.null T.lines T.unpack diff --git a/src/Data/Text/Zipper/Generic.hs b/src/Data/Text/Zipper/Generic.hs --- a/src/Data/Text/Zipper/Generic.hs +++ b/src/Data/Text/Zipper/Generic.hs @@ -24,6 +24,7 @@ init :: a -> a null :: a -> Bool lines :: a -> [a] + toList :: a -> [Char] instance GenericTextZipper [Char] where singleton = (:[]) @@ -34,6 +35,7 @@ init = Prelude.init null = Prelude.null lines = Prelude.lines + toList = id instance GenericTextZipper T.Text where singleton = T.singleton @@ -44,6 +46,7 @@ init = T.init null = T.null lines = T.lines + toList = T.unpack instance GenericTextZipper (V.Vector Char) where singleton = V.singleton @@ -54,8 +57,9 @@ init = V.init null = V.null lines = V.vecLines + toList = V.toList textZipper :: GenericTextZipper a => [a] -> Maybe Int -> TextZipper a textZipper = - mkZipper singleton drop take length last init null lines + mkZipper singleton drop take length last init null lines toList diff --git a/text-zipper.cabal b/text-zipper.cabal --- a/text-zipper.cabal +++ b/text-zipper.cabal @@ -1,5 +1,5 @@ name: text-zipper -version: 0.8.3 +version: 0.9 synopsis: A text editor zipper library description: This library provides a zipper and API for editing text. license: BSD3