attosplit (empty) → 0.0.1

raw patch · 4 files changed

+190/−0 lines, 4 filesdep +attoparsecdep +basedep +bytestringsetup-changed

Dependencies added: attoparsec, base, bytestring

Files

• Data/Attoparsec/Split.hs +83/−0
• LICENSE +29/−0
• Setup.hs +2/−0
• attosplit.cabal +76/−0

@@ -0,0 +1,83 @@+-----------------------------------------------------------------------------+-- |+-- Module      :  Data.Attoparsec.Split+-- Copyright   :  2010 Suite Solutions Ltd., Israel+--+-- Maintainer  :  Yitz Gale <yitzg@suite-sol.com>+-- Portability :  portable+--+-- Split a lazy bytestring into a lazy list of lazy bytestrings at+-- boundaries defined by an attoparsec parser. The result of+-- a matching parse is included at the beginning of the+-- lazy bytestring which begins at that point.++{- Copyright (c) 2010 Suite Solutions Ltd., Israel. All rights reserved.+For licensing information, see the BSD3-style license in the file+LICENSE that was originally distributed by the author together with+this file. -}++module Data.Attoparsec.Split (split) where++import Data.Attoparsec (Parser, Result(..), parse)+import Data.ByteString.Lazy.Internal (ByteString(..), chunk)+import qualified Data.ByteString.Lazy as Lazy+import qualified Data.ByteString as B+import qualified Data.ByteString as Strict+import Data.Maybe (fromMaybe, isJust)++-- The result of examining the next group of bytes in the input stream+data SplitResult =+    -- A match of the parser, ending the current lazy bytestring+    Match !B.ByteString -- The result of the match, to be used as+                        -- the prefix for the next component+          !ByteString   -- The rest of the input after the match+          !Bool         -- Did the match consume any input?+  | SplitChunk !B.ByteString -- A chunk of the current lazy bytestring+  deriving Show++isChunk :: SplitResult -> Bool+isChunk (SplitChunk _) = True+isChunk _              = False++asChunk :: SplitResult -> B.ByteString+asChunk (SplitChunk c) = c+asChunk _              = B.empty++-- | Split a lazy bytestring at boundaries defined by an attoparsec parser.+split :: Parser Strict.ByteString -> Lazy.ByteString -> [Lazy.ByteString]+split bdry = firstSplit . splitOne True bdry+  where+    firstSplit []                       = []+    firstSplit result@(Match _ _ _ : _) = continue result+    firstSplit result                   = nextSplit B.empty result++    nextSplit pfx result =+      chunk pfx (foldr (chunk . asChunk) Empty result) :+      continue (dropWhile isChunk result)++    continue (Match pfx xs bump : _) = nextSplit pfx (splitOne bump bdry xs)+    continue _                       = []++-- Split off the chunks of the first lazy bytestring from the input.+-- If the previous parser match did not consume any input, pass the+-- first byte through and only start looking for further parser matches+-- at the second byte.+-- A Match element will only occur as the last element of the result list.+-- If the last element is not a Match, end of input was reached.+splitOne :: Bool -> (Parser B.ByteString) -> ByteString -> [SplitResult]+splitOne _    _    Empty        = []+splitOne bump bdry (Chunk x xs)+ | bump                         = go 0 Nothing . parse bdry $ x+ | otherwise                    = go 1 Nothing . parse bdry $ B.tail x+  where+    go n _ (Fail _ _ _)+     | n < B.length x     = let n' = n + 1+                            in go n' Nothing . parse bdry $ B.drop n' x+     | otherwise          = SplitChunk x : splitOne True bdry xs+    go n ys (Done x' pfx) = [SplitChunk $ B.take n x,+                             Match pfx (chunk x' $ fromMaybe xs ys) $+                               isJust ys || B.length x' < B.length x - n]+    go n ys (Partial k)   = goPartial n (fromMaybe xs ys) k++    goPartial n (Chunk y ys) k = go n (Just ys) $ k y+    goPartial n _            _ = go n Nothing $ Fail B.empty [] ""

@@ -0,0 +1,29 @@+Copyright (c) 2010 Suite Solutions Ltd., Israel. All rights reserved.++Redistribution and use in source and binary forms, with or without+modification, are permitted provided that the following conditions are met:++    * Redistributions of source code must retain the above copyright+      notice, this list of conditions and the following disclaimer.++    * Redistributions in binary form must reproduce the above+      copyright notice, this list of conditions and the following+      disclaimer in the documentation and/or other materials provided+      with the distribution.++    * Neither the name of Yitzchak Gale nor the name Suite Solutions+      nor the names of other contributors may be used to endorse or+      promote products derived from this software without specific+      prior written permission.++THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR+A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT+OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,+DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY+THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

@@ -0,0 +1,2 @@+import Distribution.Simple+main = defaultMain

@@ -0,0 +1,76 @@+-- attosplit.cabal auto-generated by cabal init. For additional+-- options, see+-- http://www.haskell.org/cabal/release/cabal-latest/doc/users-guide/authors.html#pkg-descr.+-- The name of the package.+Name:                attosplit++-- The package version. See the Haskell package versioning policy+-- (http://www.haskell.org/haskellwiki/Package_versioning_policy) for+-- standards guiding when and how versions should be incremented.+Version:             0.0.1++-- A short (one-line) description of the package.+Synopsis:+  Split a lazy bytestring at boundaries defined by an attoparsec parser++-- A longer description of the package.+Description:+  Split a lazy bytestring into a lazy list of lazy bytestrings at+  boundaries defined by an attoparsec parser. The result of+  a matching parse is included at the beginning of the+  lazy bytestring which begins at that point.++-- URL for the project homepage or repository.+Homepage:            http://projects.haskell.org/attosplit++-- The license under which the package is released.+License:             BSD3++-- The file containing the license text.+License-file:        LICENSE++-- The package author(s).+Author:              Yitzchak Gale++-- An email address to which users can send suggestions, bug reports,+-- and patches.+Maintainer:          yitz@community.haskell.org++-- A copyright notice.+Copyright:+  Copyright (c) 2010 Suite Solutions Ltd., Israel. All rights reserved.++Category:            Data++Build-type:          Simple++-- Extra files to be distributed with the package, such as examples or+-- a README.+-- Extra-source-files:++-- Constraint on the version of Cabal needed to build this package.+Cabal-version:       >=1.6+++Library+  -- Modules exported by the library.+  Exposed-modules:     Data.Attoparsec.Split++  -- Packages needed in order to build this package.+  Build-depends:+    base >= 3 && < 5,+    attoparsec == 0.8.*,+    bytestring == 0.9.*++  -- Modules not exported by this package.+  -- Other-modules:++  -- Extra tools (e.g. alex, hsc2hs, ...) needed to build the source.+  -- Build-tools:++  GHC-options: -O2 -Wall+  GHC-prof-options: -auto-all++Source-repository HEAD+  Type:     darcs+  Location: http://code.haskell.org/attosplit