Ticket #2048: splitWith.patch

New patches:

[Add split and splitWith to Data.List
Twan van Laarhoven <twanvl@gmail.com>**20080116225312] {
hunk ./Data/List.hs 103
+   -- Breaking into many substrings
+   , split             -- :: Eq a => a -> [a] -> [[a]]
+   , splitWith         -- :: (a -> Char) -> [a] -> [[a]]
+
hunk ./Data/List.hs 737
+-- | Break a list into pieces separated by the argument,
+-- consuming the delimiter. I.e.
+--
+-- > split '\n' "a\nb\nd\ne" == ["a","b","d","e"]
+-- > split 'a'  "aXaXaXa"    == ["","X","X","X",""]
+-- > split 'x'  "x"          == ["",""]
+split                   :: Eq a => a -> [a] -> [[a]]
+split x                 =  splitWith (x==)
+
+-- | Splits a 'list into components delimited by separators,
+-- where the predicate returns True for a separator element.
+-- The resulting components do not contain the separators.
+-- Two adjacent separators result in an empty component in the output.
+splitWith               :: (a -> Bool) -> [a] -> [[a]]
+splitWith p xs          =  ys : case zs of
+                                  []   -> []
+                                  _:ws -> splitWith p ws
+                           where (ys,zs) = break p xs
+
}

Context:

[Data.List.sort: force elements from start to end.
Bertram Felgenhauer <int-e@gmx.de>**20071121101458
 this prevents a stack overflow on  sort (take 10^6 [1..])
] 
[Fix comment on GHC.Ptr.minusPtr
simonpj@microsoft.com**20080109114736] 
[Remove redundant imports of GHC.Err
simonpj@microsoft.com**20080104091314
 
 GHC.Base SOURCE-imports GHC.Err, and re-exports 'error'.  So 
 other modules need only import GHC.Base.
 
 This doesn't change the fact that these other modules are all compiled
 before GHC.Err, so they are all part of the module loop that starts with
 GHC.Base and finishes with GHC.Err.  But it does reduce the occurrence
 of those SOURCE imports.
 
] 
[Tuple tycons have parens around their names
simonpj@microsoft**20071220171812
 
 The name of the pair TyCon, in the Typeable instance,
 should be "(,)" not ",".
 
 Don't merge to 6.8; it's a minor API change. 
 
] 
[Add groupWith, sortWith, the, to support generalised list comprehensions
simonpj@microsoft.com**20071220111929
 
   This the base-library patch to support the main compiler patch
      Implement generalised list comprehensions
   
   It just adds three functions to GHC.Exts.
 
] 
[Add GHC.Prim to exposedModules in the Haddock 0.x hook
David Waern <david.waern@gmail.com>*-20071209173931
 
 Please merge to the stable branch
] 
[Add GHC.Prim to exposedModules in the Haddock 0.x hook
David Waern <david.waern@gmail.com>**20071209173931
 
 Please merge to the stable branch
] 
[Simplify the GHC.Prim hack in base.cabal/Setup.hs
Ian Lynagh <igloo@earth.li>**20071202215758] 
[Implement 'openTempFile' for nhc98.
Malcolm.Wallace@cs.york.ac.uk**20071207133335] 
[docs: describe the changes to forkIO, and document forkOnIO
Simon Marlow <simonmar@microsoft.com>**20071205091423] 
[doc only: use realToFrac instead of fromRational.toRational
Simon Marlow <simonmar@microsoft.com>**20071205091334] 
[Add singletonP to GHC.PArr
Roman Leshchinskiy <rl@cse.unsw.edu.au>**20071205220859] 
[FIX #1621: bug in Windows code for getCPUTime
Simon Marlow <simonmar@microsoft.com>**20071205120118
 We were reading the components of FILETIME as CLong, when they should
 be unsigned.  Word32 seems to be the correct type here.
] 
[protect console handler against concurrent access (#1922)
Simon Marlow <simonmar@microsoft.com>**20071204153940] 
[protect against concurrent access to the signal handlers (#1922)
Simon Marlow <simonmar@microsoft.com>**20071204110817] 
[restore fdToHandle' to avoid breaking clients (#1109)
Simon Marlow <simonmar@microsoft.com>**20071130135122
 
] 
[note about how to convert CTime (aka EpochTime) to UTCTime
Simon Marlow <simonmar@microsoft.com>**20071130101648] 
[Fix some URLs
Ian Lynagh <igloo@earth.li>**20071126214213] 
[Fix some links in haddock docs
Ian Lynagh <igloo@earth.li>**20071126184428] 
[Don't try to make haddock links to the mtl package as we don't depend on it
Ian Lynagh <igloo@earth.li>**20071126170631] 
[Escape some special characters in haddock docs
Ian Lynagh <igloo@earth.li>**20071126163443] 
[FIX BUILD: maybeUpdateFile: ignore failures when removing the target
Simon Marlow <simonmar@microsoft.com>**20071123092219] 
[FIX #1753
Simon Marlow <simonmar@microsoft.com>**20071122094207
 hClose should close the Handle and unlock the file even if calling
 close() fails for some reason.
] 
[remove lockFile.h from install-includes
Simon Marlow <simonmar@microsoft.com>**20071121102248] 
[oops, we forgot to export traceShow
Simon Marlow <simonmar@microsoft.com>**20071121094300] 
[Fix compilation with GHC 6.2.x
Simon Marlow <simonmar@microsoft.com>**20071121084341] 
[Move file locking into the RTS, fixing #629, #1109
Simon Marlow <simonmar@microsoft.com>**20071120121053
 File locking (of the Haskell 98 variety) was previously done using a
 static table with linear search, which had two problems: the array had
 a fixed size and was sometimes too small (#1109), and performance of
 lockFile/unlockFile was suboptimal due to the linear search.
 Also the algorithm failed to count readers as required by Haskell 98
 (#629).
 
 Now it's done using a hash table (provided by the RTS).  Furthermore I
 avoided the extra fstat() for every open file by passing the dev_t and
 ino_t into lockFile.  This and the improvements to the locking
 algorithm result in a healthy 20% or so performance increase for
 opening/closing files (see openFile008 test).
] 
[Only overwrite GHC/Prim.hs and GHC/Primopwrappers.hs if they change
Simon Marlow <simonmar@microsoft.com>**20071120102042
 This avoids make doing unnecessary work after 'setup makefile'.
] 
[fix comment
Simon Marlow <simonmar@microsoft.com>**20071116091227] 
[Fix ` characters in elem's haddock docs
Ian Lynagh <igloo@earth.li>**20071110173052] 
[Filter out GHC.Prim also for the Haddock step
David Waern <david.waern@gmail.com>**20071109000806
 Please merge to the GHC 6.8.2 branch
] 
[Add module of special magic GHC desugaring helper functions
Simon Marlow <simonmar@microsoft.com>**20071102160054
 Currently containing only one such helper: (>>>) for arrow desugaring
] 
[add Control.Category to the nhc98 build
Malcolm.Wallace@cs.york.ac.uk**20071030120459] 
[fix nhc98 build: need a qualified Prelude import
Malcolm.Wallace@cs.york.ac.uk**20071030120410] 
[Fix performance regression: re-instate -funbox-strict-fields
Simon Marlow <simonmar@microsoft.com>**20071029150730
 Yikes!  While investigating the increase in code size with GHC 6.8
 relative to 6.6, I noticed that in the transition to Cabal for the
 libraries we lost -funbox-strict-fields, which is more or less
 depended on by the IO library for performance.  I'm astonished that we
 didn't notice this earlier!
 
 To reduce the chances of this happening again, I put
 -funbox-strict-fields in the OPTIONS_GHC pragma of the modules that
 need it.  {-# UNPACK #-} pragmas would be better, though.
] 
[FIX BUILD: Haddock 1.x fails to parse (Prelude..)
Simon Marlow <simonmar@microsoft.com>**20071029131921] 
[new Control.Category, ghc ticket #1773
Ashley Yakeley <ashley@semantic.org>**20071029022526] 
[new Control.Compositor module
Ashley Yakeley <ashley@semantic.org>**20071013074851
 
 The Compositor class is a superclass of Arrow.
] 
[Fix doc building with Haddock 0.9
Simon Marlow <simonmar@microsoft.com>**20071024090947
 I was using a recent build here, which is more tolerant.
] 
[FIX #1258: document that openTempFile is secure(ish)
Simon Marlow <simonmar@microsoft.com>**20071023130928
 Also change the mode from 0666 to 0600, which seems like a more
 sensible value and matches what C's mkstemp() does.
] 
[Clean up .cabal file a bit
Duncan Coutts <duncan@haskell.org>**20071022132708
 specify build-type and cabal-version >= 1.2
 put extra-tmp-files in the right place
 use os(windows) rather than os(mingw32)
] 
[base in 6.8 and head branch should be version 3.0
Don Stewart <dons@galois.com>**20071007150408] 
[FIX #1652: openTempFile should accept an empty string for the directory
Simon Marlow <simonmar@microsoft.com>**20071018122345] 
[clean up duplicate code
Simon Marlow <simonmar@microsoft.com>**20071017141311] 
[expose the value of +RTS -N as GHC.Conc.numCapabilities (see #1733)
Simon Marlow <simonmar@microsoft.com>**20071009132042] 
[typo
Simon Marlow <simonmar@microsoft.com>**20070917130703] 
[put extra-tmp-files field in the right place
Simon Marlow <simonmar@microsoft.com>**20070914140812] 
[Add more entries to boring file
Ian Lynagh <igloo@earth.li>**20070913210500] 
[Add a boring file
Ian Lynagh <igloo@earth.li>**20070913204641] 
[TAG 2007-09-13
Ian Lynagh <igloo@earth.li>**20070913215720] 
Patch bundle hash:
a893748312577bccfa707a1be006cb6d81a7316a