+++ /dev/null
-Release~0.26 is a major public release of Glasgow Haskell.
-It incorporates our new work for the first half of 1995.
-
-The announcement for this release is distributed as \tr{ANNOUNCE-0.26}
-in the top-level directory.
-
-You'll need to recompile everything if you're switching from a
-previous version of GHC. (If you don't, you'll get ``consistency
-errors''.) Some day, we will stop doing this to you :-)
-
-Information about ``what's ported to which machine'' is now given in
-the Installation Guide.
-The new ports since 0.23 are: \tr{hppa1.1-hp-hpux},
-\tr{i386-*-linuxaout}, and \tr{mips-sgi-irix5}.
-
-%************************************************************************
-%* *
-\subsection[0-26-config]{New configuration things in 0.26}
-%* *
-%************************************************************************
-
-We are moving towards one \tr{configure} script for all Glasgow
-functional-programming tools. Consequently, the configure options
-have been tweaked. Doing \tr{./configure --help} will show you the
-current state of play.
-
-%************************************************************************
-%* *
-\subsection[0-26-user-visible]{User-visible changes in 0.26, including incompatibilities}
-%* *
-%************************************************************************
-
-The names \tr{scc}, \tr{ccall}, and \tr{casm} are no longer stolen
-from the user's name space. (The magical constructs they once were
-have been known as \tr{_scc_}, \tr{_ccall_}, and \tr{_casm_} for some
-time now...)
-
-Similarly, \tr{trace} is no longer built-in (so you can use the name
-if you want to). You can get \tr{trace} either as \tr{_trace}
-(Glasgow extension), or as itself via \tr{import Trace} with
-\tr{-syslib hbc} (i.e., exactly like HBC).
-
-Lazy, or irrefutable, patterns with unboxed-type components are
-no longer allowed. You'll need to rewrite \tr{let (I# x) = exp ...}
-as \tr{let x = case exp of { I# i -> i } in ... }.
-
-GHC now supports hexadecimal and octal numeric syntax for integer constants.
-(But \tr{read} doesn't grok it yet...)
-
-GHC now supports specialised instances (as in HBC); you can write:
-\begin{verbatim}
-instance Eq a => Eq (Foo a) where { ... }
-{-# SPECIALIZE instance Eq (Foo Bool) #-}
-\end{verbatim}
-
-GHC's pragmas for specialised values now have a magical \tr{= blah}
-form, in which you specify the code to be used for the specialised value.
-For example:
-\begin{verbatim}
-f :: Ord a => a -> Int -> a
-{-# SPECIALIZE f :: Double -> Int -> Double = f_Double #-}
-
-f_Double :: Double -> Int -> Double
-f_Double ...
-\end{verbatim}
-In some cases, the \tr{= blah} form can be a {\em big} win.
-
-What we used to call ``threaded'' Haskell, we now call ``Concurrent
-Haskell.'' And there's a paper about it. Please see the User's Guide.
-
-``Parallel Haskell,'' running under PVM, is here. Again, see the
-User's Guide.
-
-%************************************************************************
-%* *
-\subsection[0-26-options]{New or changed GHC command-line options}
-%* *
-%************************************************************************
-
-The \tr{-g}, \tr{-p}, \tr{-pg}, \tr{-fpic}, and \tr{-fPIC} are no
-longer passed straight through to GCC. They probably buy you nothing,
-while potentially causing substantial mischief. If you know what you're doing,
-you can still use them, via \tr{-optcO-...}.
-
-The main option for Concurrent Haskell is \tr{-concurrent}; for
-Parallel Haskell, it's \tr{-parallel}.
-
-The \tr{-dict-all} option, used with \tr{-prof}, has died. It never
-did anything anyway.
-
-Besides the \tr{-fshow-specialisations} option to see what specialisations
-have occurred, you may also use the \tr{-fshow-import-specs} option
-to see what specialisations GHC would like to have had available.
-By then adding these ``desirable'' pragmas to your code, you can
-squash most of the overloading from your program.
-
-There are some new sanity-checking options. Use
-\tr{-fsignatures-required} if you want to force all top-level
-definitions to have type signatures. Use \tr{-fshadowing-not-ok}
-if you want to disallow name shadowing. You can't use the latter on
-modules that include circular definitions.
-
-The \tr{-Rghc-timing} option gives a convenient one-line summary to
-GHC's runtime and heap allocation.
-
-The \tr{-odump} option may be used to save GHC's standard-error output
-to a file. (It normally shows up on your screen.)
-
-You can now use \tr{-H0} and \tr{-K0} to reset the heap and stack
-sizes. As these sizes are normally ``maxxed up'' (\tr{-H32m -H16m}
-gets you a 32MB heap), you can use this form to decrease the size:
-\tr{-H6m -H0 -H250k} gives you a heap of 250KB.
-
-%************************************************************************
-%* *
-\subsection[0-26-io]{New in monadic I/O}
-%* *
-%************************************************************************
-
-GHC~0.26 is still a Haskell~1.2 compiler (and will remain so until
-there is a non-DRAFT 1.3 standard).
-
-We killed the \tr{PreludePrimIO} interface. You can get all the same
-functions from \tr{PreludeGlaST}.
-
-All the \tr{_IVar} and \tr{_MVar} operations are now in the 1.3
-\tr{IO} monad, not the non-standard \tr{PrimIO} monad. You now
-get them from \tr{Concurrent}, not from \tr{PreludeGlaST}.
-
-%************************************************************************
-%* *
-\subsection[0-26-new-in-compiler]{New in the compiler proper}
-%* *
-%************************************************************************
-
-The main new things are ``foldr-build'' deforestation (by Andy Gill)
-and ever-more-glorious specialisation (by Patrick Sansom).
-
-And the usual few megabytes of gratuitous changes.
-
-%************************************************************************
-%* *
-\subsection[0-26-new-in-libraries]{In the prelude and libraries}
-%* *
-%************************************************************************
-
-All of the basic state-transformer stuff now comes from
-\tr{PreludeGlaST}. The \tr{PreludePrimIO} interface no longer exists.
-
-The function \tr{foldrPrimIO} went away. The function \tr{forkPrimIO}
-sprang to life.
-
-The what-you-need-for-Concurrent-Haskell interface is \tr{Concurrent}.
-The GHC option is \tr{-concurrent}. Please see the User's Guide.
-Note that the operations @threadDelay@ and @threadWait@ now come
-from \tr{Concurrent}, not \tr{PreludeGlaMisc}.
-
-I-Vars and M-Vars (synchronising variables) are now
-specifically I/O operations, not general state-transformer operations.
-They also come from the \tr{Concurrent} interface.
-
-Renamings: what used to be the \tr{newMVar} operation is now called
-\tr{newEmptyMVar}; what was \tr{initMVar} is now \tr{newMVar}.
-
-The what-you-need-for-Parallel-Haskell interface is \tr{Parallel}.
-The GHC option is \tr{-parallel}. At the moment, the \tr{Parallel}
-interface just provides \tr{par} and \tr{seq}. But that will change.
-
-\tr{LibPosix} now provides \tr{runProcess}, our candidate for the
-high-level OS-independent operation.
-
-NEW: The \tr{Regex} (\tr{-syslib ghc}) interface provides direct
-access to the GNU regexp (regular expressions on strings) package.
-The \tr{MatchPS} interface is higher-level, providing string-matching
-functions on \tr{_PackedStrings}. (All by Sigbjorn Finne)
-
-NEW: The \tr{Readline} interface (also \tr{-syslib ghc}) provides
-access to the GNU readline package. Instant command-line editing
-for your Haskell programs. (By Darren Moffat)
-
-NEW: A ``network interface toolkit'' by Darren Moffat. BSD sockets
-for Haskell---way cool.
-
-The \tr{FiniteMap} module has two new functions, \tr{isEmptyFM} and
-\tr{elemFM}.
-
-The \tr{Maybes} module now uses the Haskell~1.3 built-in \tr{Maybe}
-type; you should use \tr{-fhaskell-1.3} with this module now.
-
-The HBC library modules \tr{Maybe}, \tr{Either}, and \tr{Option} are
-{\em gone}. Just use \tr{-fhaskell-1.3} and get the types directly
-from the Prelude.
-
-All system-library modules that use the \tr{Maybe} type now require
-\tr{-fhaskell-1.3}. For the GHC library, that means \tr{FiniteMap},
-\tr{Maybes}, \tr{Util}, \tr{Set}, \tr{Regex}, and \tr{MatchPS}. For
-the HBC library, that means \tr{ListUtil}, \tr{Native}, and
-\tr{Parse}. (In some cases, you could avoid the \tr{-fhaskell-1.3}
-requirement by doing selective imports.)
-
-GHC now supports \tr{trace} exactly like HBC: \tr{import Trace} and
-do \tr{-syslib hbc}. The built-in no-import-required version
-is now called \tr{_trace}.
-
-Instances for \tr{Shorts} and \tr{Bytes} have been added to the
-HBC library module \tr{Word}.
-
-As part of the GHC system library, we now provide an interface to the
-GNU regexp (regular-expression) library; the \tr{Regexp} interface.
-A higher-level interface, to do matches on \tr{_PackedString}s comes
-from the \tr{MatchPS} interface.
-
-We no longer provide specialisations of Prelude functions to the
-\tr{Float} type; only to \tr{Double}. It saves space, and we want to
-discourage the use of single-precision floating-point.
-
-%************************************************************************
-%* *
-\subsection[0-26-new-in-rts]{In the runtime system}
-%* *
-%************************************************************************
-
-GHC now supplies some very simple ``hooks'' to let you change the
-failure messages for stack and heap overflow, \tr{error}, and
-pattern-matching failure. Please see the User's Guide.
-
-You can now force garbage collection after every N bytes of allocation
-(presumably for stats collection, or something). Use the \tr{-j} RTS
-option.
-
-``Squeezing out'' update frames at garbage-collection time is now {\em
-on} by default. (You can turn it off with the \tr{-Z} RTS option, but
-I can't think why you would want to.)
-
-%************************************************************************
-%* *
-\subsection[0-26-new-elsewhere]{Other new stuff}
-%* *
-%************************************************************************
-
-The GHC distribution now includes an ``examples'' directory, including
-a simple shell (\tr{hsh} and quite a few to do with 1.3 I/O
-(\tr{ioNNN}) and \tr{LibPosix} (\tr{poNNN}). All in
-\tr{ghc/misc/examples}...
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