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diff --git a/docs/users_guide/8.0.1-notes.rst b/docs/users_guide/8.0.1-notes.rst deleted file mode 100644 index 5b10a32b7b..0000000000 --- a/docs/users_guide/8.0.1-notes.rst +++ /dev/null @@ -1,796 +0,0 @@ -.. _release-8-0-1: - -Release notes for version 8.0.1 -=============================== - -The significant changes to the various parts of the compiler are listed -in the following sections. There have also been numerous bug fixes and -performance improvements over the 7.10 branch. - -.. warning:: - - Only Cabal versions 1.24 and newer will function properly with this release. - (see :ghc-ticket:`11558`). Consequently it will likely be necessary to - recompile ``cabal-install`` before installing new packages. - - The reason for this is a change in how packages are identified in GHC - 8.0. While previous versions of Cabal identified packages to GHC with a - package key (with GHC's :ghc-flag:`-this-package-key` argument), GHC 8.0 and - later uses installed package IDs in place of package keys. - -.. note:: - - Users compiling GHC on Mac OS X with XCode 7.3 will need to tell the build - system to use the ``nm-classic`` command instead of Apple's new ``nm`` - implementation as the latter breaks POSIX compliance (see - :ghc-ticket:`11744`). This can be done by passing something like - ``--with-nm=$(xcrun --find nm-classic)`` to ``configure``. - -Highlights ----------- - -The highlights, since the 7.10 branch, are: - -- TODO FIXME - -- The new :ghc-flag:`-XTypeInType` allows promotion of all types into - kinds, allowing kind synonyms, kind families, promoted GADTs, and other - goodies. - -- Support for :ref:`record pattern synonyms <record-patsyn>` - -- The :ghc-flag:`-XDeriveAnyClass` extension learned to derive instances for - classes with associated types (see :ref:`derive-any-class`) - -- More reliable DWARF debugging information - -- Support for :ref:`injective type families <injective-ty-fams>` - -- Applicative ``do`` notation (see :ref:`applicative-do`) - -- Support for wildcards in data and type family instances - -- :ghc-flag:`-XStrict` and :ghc-flag:`-XStrictData` extensions, allowing modules - to be compiled with strict-by-default bindings (see :ref:`strict-haskell`) - -- :ghc-flag:`-XDuplicateRecordFields`, allowing multiple datatypes to declare the same - record field names provided they are used unambiguously (see :ref:`duplicate-record-fields`) - -- Support for lightweight - :ref:`callstacks and source locations <hascallstack>` - -- User-defined error messages for type errors - -- A rewritten (and greatly improved) pattern exhaustiveness checker - -- More flexible rebindable syntax - -- GHC can run the interpreter in a separate process (see - :ref:`external-interpreter`), and the interpreter can now run profiled - code. - -- GHCi now provides access to stack traces when used with - :ghc-flag:`-fexternal-interpreter` and :ghc-flag:`-prof` (see - :ref:`ghci-stack-traces`). - -- A native code generator for powerpc64 and powerpc64le architectures - -- The reworked users guide you are now reading - -- Support for Windows XP and earlier has been dropped. - -- GHC RTS No longer re-exports POSIX functions under their deprecated - names on Windows. - -Full details ------------- - -Language -~~~~~~~~ - -- TODO FIXME. - -- :ghc-flag:`-XTypeInType` supports universal type promotion and merges - the type and kind language. This allows, for example, higher-rank - kinds, along with kind families and type-level GADTs. Support is still - experimental, and it is expected to improve over the next several - releases. See :ref:`type-in-type` for the details. - -- The parser now supports Haddock comments on GADT data constructors. - For example :: - - data Expr a where - -- | Just a normal sum - Sum :: Int -> Int -> Expr Int - -- The new ``base`` constraint :base-ref:`GHC.Stack.HasCallStack <GHC-Stack.html>` - can be used by functions to request a partial call-stack. For example :: - - errorWithCallStack :: HasCallStack => String -> a - errorWithCallStack msg = error (msg ++ "\n" ++ prettyCallStack callStack) - - ghci> errorWithCallStack "die" - *** Exception: die - CallStack (from HasCallStack): - errorWithCallStack, called at <interactive>:2:1 in interactive:Ghci1 - - prints the call-site of ``errorWithCallStack``. - - See :ref:`hascallstack` for a description of ``HasCallStack``. - -- GHC now supports visible type application, allowing - programmers to easily specify how type parameters should be - instantiated when calling a function. See - :ref:`visible-type-application` for the details. - -- To conform to the common case, the default role assigned to - parameters of datatypes declared in ``hs-boot`` files is - ``representational``. However, if the constructor(s) for the datatype - are given, it makes sense to do normal role inference. This is now - implemented, effectively making the default role for non-abstract - datatypes in ``hs-boot`` files to be ``phantom``, like it is in - regular Haskell code. - -- Wildcards can be used in the type arguments of type/data family - instance declarations to indicate that the name of a type variable - doesn't matter. They will be replaced with new unique type variables. - See :ref:`data-instance-declarations` for more details. - -- GHC now allows to declare type families as injective. Injectivity - information can then be used by the typechecker. See - :ref:`injective-ty-fams` for details. - -- Due to a :ghc-ticket:`security issue <10826>`, Safe Haskell now forbids - annotations in programs marked as :ghc-flag:`-XSafe`. - -- Generic instances can be derived for data types whose constructors have - arguments with certain unlifted types. See :ref:`generic-programming` for - more details. - -- GHC generics can now provide strictness information for fields in a data - constructor via the ``Selector`` type class. - -- The :ghc-flag:`-XDeriveAnyClass` extension now fills in associated type family - default instances when deriving a class that contains them. - -- The :ghc-flag:`-XRebindableSyntax` feature is now much more flexible, imposing - fewer restrictions on the types of the rebindable syntax elements. For example, - your ``negate`` function may now return a different type than it accepts. - Rebindable syntax also supports higher-rank types fully, allowing types - like ``(>>=) :: m a -> (forall x. a x -> m b) -> m b``. - -- Users can now define record pattern synonyms. This allows pattern synonyms - to behave more like normal data constructors. For example, :: - - pattern P :: a -> b -> (a, b) - pattern P{x,y} = (x,y) - - will allow ``P`` to be used like a record data constructor and also defines - selector functions ``x :: (a, b) -> a`` and ``y :: (a, b) -> b``. - -- Pattern synonyms can now be bundled with type constructors. For a pattern - synonym ``P`` and a type constructor ``T``, ``P`` can be bundled with ``T`` - so that when ``T`` is imported ``P`` is also imported. With this change - a library author can provide either real data constructors or pattern - synonyms in an opaque manner. See :ref:`pattern-synonyms` for details. :: - - -- Foo.hs - module Foo ( T(P) ) where - - data T = T - - pattern P = T - - -- Baz.hs - module Baz where - - -- P is imported - import Foo (T(..)) - -- Whenever a data instance is exported, the corresponding data family - is exported, too. This allows one to write :: - - -- Foo.hs - module Foo where - - data family T a - - -- Bar.hs - module Bar where - - import Foo - - data instance T Int = MkT - - -- Baz.hs - module Baz where - - import Bar (T(MkT)) - - In previous versions of GHC, this required a workaround via an - explicit export list in ``Bar``. - -- GHC has grown a :ghc-flag:`-XUndecidableSuperClasses` language extension, - which relaxes GHC's recursive superclass check (see :ghc-ticket:`11318`). - This allows class definitions which have mutually recursive superclass - constraints at the expense of potential non-termination in the solver. - -- The compiler is now a bit more conservative in solving constraints previously - provided by superclasses (see :ghc-ticket:`11762`). For instance, consider - this program,:: - - {-# LANGUAGE FlexibleInstances #-} - {-# LANGUAGE UndecidableInstances #-} - - class Super a - class (Super a) => Left a - class (Super a) => Right a - instance (Left a) => Right a -- this is now an error - - GHC now rejects this instance, claiming it cannot deduce the ``Super a`` - superclass constraint of the ``Right`` typeclass. This stands in contrast to - previous releases, which would accept this declaration, using the ``Super a`` - constraint implied by the ``Left a`` constraint. To fix this simply add the - needed superclass constraint explicitly, :: - - instance (Left a, Super a) => Right a - -- :ghc-flag:`-XDeriveFoldable` and :ghc-flag:`-XDeriveTraversable` now - generate code without superfluous ``mempty`` or ``pure`` expressions. As a - result, :ghc-flag:`-XDeriveTraversable` now works on datatypes that contain - arguments which have unlifted types. - -- Note that the :ghc-flag:`-XImpredicativeTypes` extension, which has been - :ghc-wiki:`known <ImpredicativePolymorphism>` to be broken for many years, is even more - broken than usual in this release (see :ghc-ticket:`11319`, - :ghc-ticket:`11675`, and others). During pre-release testing we encountered - a number of projects that broke with confusing type errors due to (often - unnecessary) use of :ghc-flag:`-XImpredicativeTypes`. Users of - :ghc-flag:`-XImpredicativeTypes` do so at their own risk! - -Compiler -~~~~~~~~ - -- The LLVM code generator now supports only LLVM 3.7. This is in contrast to our - previous policy where GHC would try to support a range of LLVM versions - concurrently. We hope that by supporting a narrower range of versions we can - provide more reliable support for each. - -- Warnings can now be controlled with ``-W(no-)...`` flags in addition to - the old ``-f(no-)warn...`` ones. This was done as the first part of a - rewrite of the warning system to provide better control over warnings, - better warning messages, and more common syntax compared to other - compilers. The old ``-f``-based warning flags will remain functional for - the forseeable future. - -- Added the option :ghc-flag:`-dth-dec-file`. This dumps out a ``.th.hs`` file of - all Template Haskell declarations in a corresponding .hs file. The - idea is that application developers can check this into their - repository so that they can grep for identifiers used elsewhere that - were defined in Template Haskell. This is similar to using - :ghc-flag:`-ddump-to-file` with :ghc-flag:`-ddump-splices` but it always generates a - file instead of being coupled to :ghc-flag:`-ddump-to-file` and only outputs - code that does not exist in the .hs file and a comment for the splice - location in the original file. - -- After a long hiatus (see :ghc-ticket:`10935`) the - :ghc-flag:`-Wmonomorphism-restriction` (formerly - :ghc-flag:`-fwarn-monomorphism-restriction`) flag has returned. - The functionality of this flag was inadvertently removed by a commit in 2010; - this has been fixed and the flag should now issue warnings as it - previously did. - -- Added the option :ghc-flag:`-fprint-expanded-types`. When enabled, GHC also - prints type-synonym-expanded types in type errors. - -- Added the option :ghc-flag:`-fcpr-anal`. When enabled, the demand analyser - performs CPR analysis. It is implied by :ghc-flag:`-O`. Consequently, - :ghc-flag:`-fcpr-off` is now removed, run with :ghc-flag:`-fno-cpr-anal` to get the - old :ghc-flag:`-fcpr-off` behaviour. - -- Added the option :ghc-flag:`-fworker-wrapper`. When enabled, the worker-wrapper - transformation is performed after a strictness analysis pass. It is implied - by :ghc-flag:`-O` and by :ghc-flag:`-fstrictness`. It is disabled by :ghc-flag:`-fno-strictness`. - Enabling :ghc-flag:`-fworker-wrapper` while strictness analysis is disabled (by - :ghc-flag:`-fno-strictness`) has no effect. - -- Added the options :ghc-flag:`-Wmissed-specialisations` and - :ghc-flag:`-Wall-missed-specialisations`. When enabled, the simplifier will - produce a warning when a overloaded imported function cannot be - specialised (typically due to a missing ``INLINEABLE`` pragma). This - is intended to alert users to cases where they apply ``INLINEABLE`` but - may not get the speed-up they expect. - -- Added the option :ghc-flag:`-Wnoncanonical-monad-instances` and - :ghc-flag:`-Wnoncanonical-monadfail-instances` which help detect noncanonical - ``Applicative``/``Monad``/``MonadFail`` instance definitions. - See flag description in :ref:`options-sanity` for more details. - -- When printing an out-of-scope error message, GHC will give helpful advice if - the error might be caused by too restrictive imports. - -- Added the :ghc-flag:`-Wcompat` warning group, along with its opposite - :ghc-flag:`-Wno-compat`. Turns on warnings that will be enabled by default in the - future, but remain off in normal compilations for the time being. This - allows library authors eager to make their code future compatible to adapt - to new features before they even generate warnings. - -- Added the :ghc-flag:`-Wmissing-monadfail-instances` flag. When enabled, this - will issue a warning if a failable pattern is used in a context that does - not have a ``MonadFail`` constraint. This flag represents phase 1 of the - `MonadFail Proposal (MFP) - <https://prime.haskell.org/wiki/Libraries/Proposals/MonadFail>`__. - -- Added the :ghc-flag:`-Wsemigroup` flag. When enabled, this - will issue a warning if a type is an instance of ``Monoid`` but not - ``Semigroup``, and when a custom definition ``(<>)`` is made. Fixing these - warnings makes sure the definition of ``Semigroup`` as a superclass of - ``Monoid`` does not break any code. - -- Added the :ghc-flag:`-Wmissing-pattern-synonym-signatures` - flag. When enabled, this will issue a warning when a pattern - synonym definition doesn't have a type signature. It is turned off - by default but enabled by :ghc-flag:`-Wall`. - -- Added the :ghc-flag:`-Wunused-type-patterns` flag to report unused - type variables in data and type family instances. This flag is not implied - by :ghc-flag:`-Wall`, since :ghc-flag:`-Wunused-type-patterns` will - warn about unused type variables even if the types themselves are intended - to be used as documentation. If :ghc-flag:`-Wunused-type-patterns` is - enabled, one can prefix or replace unused type variables with underscores to - avoid warnings. - -- Split off the new flag :ghc-flag:`-Wunused-foralls` from the previously - existing flag :ghc-flag:`-Wunused-matches`. :ghc-flag:`-Wunused-foralls` - emits a warning in the specific case that a user writes explicit ``forall`` - syntax with unused type variables, while :ghc-flag:`-Wunused-matches` only - warns in the case of unused term-level patterns. Both flags are implied by - :ghc-flag:`-W`. - -- Added the :ghc-flag:`-fmax-pmcheck-iterations` to control how many times - the pattern match checker iterates. Since coverage checking is exponential - in the general case, setting a default number of iterations prevents memory - and performance blowups. By default, the number of iterations is set to - 2000000 but it can be set with: ``-fmax-pmcheck-iterations=<n>``. - If the set number of iterations is exceeded, an informative warning is - issued. - -- :ghc-flag:`-this-package-key` has been renamed again (hopefully for the last time!) - to :ghc-flag:`-this-unit-id`. The renaming was motivated by the fact that - the identifier you pass to GHC here doesn't have much to do with packages: - you may provide different unit IDs for libraries which are in the same - package. :ghc-flag:`-this-package-key` is deprecated; you should use - :ghc-flag:`-this-unit-id` or, if you need compatibility over multiple - versions of GHC, :ghc-flag:`-package-name`. - -- When :ghc-flag:`-fdefer-type-errors` is enabled and an expression fails to - typecheck, ``Control.Exception.TypeError`` will now be thrown instead of - ``Control.Exception.ErrorCall``. - -- :ghc-flag:`-Wmissing-local-sigs` is now deprecated in favor of - :ghc-flag:`-Wmissing-local-signatures`. - -- :ghc-flag:`-Wmissing-exported-sigs` is now deprecated in favor of - :ghc-flag:`-Wmissing-exported-signatures`. - -- :ghc-flag:`-ddump-strsigs` has been renamed to - :ghc-flag:`-ddump-str-signatures`. - -- :ghc-flag:`-XDeriveGeneric` is now less picky about instantiating type - arguments when deriving (:ghc-ticket:`11732`). As a consequence, the - following code is now legal (whereas before it would have been rejected). :: - - data T a b = T a b - deriving instance Generic (T Int b) - -GHCi -~~~~ - -- ``Main`` with an explicit module header but without ``main`` is now - an error (:ghc-ticket:`7765`). - -- The :ghci-cmd:`:back` and :ghci-cmd:`:forward` commands now take an optional count - allowing the user to move forward or backward in history several - steps at a time. - -- Added commands :ghci-cmd:`:load! <:load>` and :ghci-cmd:`:reload! <:reload>`, - effectively setting :ghc-flag:`-fdefer-type-errors` before loading a module and - unsetting it after loading if it has not been set before (:ghc-ticket:`8353`). - -- ``ghci -e`` now behaves like :ghc-flag:`ghc -e <-e>` (:ghc-ticket:`9360`). - -- Added support for top-level function declarations (:ghc-ticket:`7253`). - -- The new commands :ghci-cmd:`:all-types`, :ghci-cmd:`:loc-at`, :ghci-cmd:`:type-at`, and - :ghci-cmd:`:uses` designed for editor-integration - (such as Emacs' ``haskell-mode``) originally premiered by ``ghci-ng`` - have been integrated into GHCi (:ghc-ticket:`10874`). - -- GHCi now supports decoupled operation between the interpreter and the - shell. While this is largely an implementation detail, it opens up a few - interesting possibilities in the future. See :ghc-wiki:`RemoteGHCi` for - details. - -Template Haskell -~~~~~~~~~~~~~~~~ - -- The new :ghc-flag:`-XTemplateHaskellQuotes` flag allows to use the - quotes (not quasi-quotes) subset of ``TemplateHaskell``. This is - particularly useful for use with a stage 1 compiler (i.e. GHC - without interpreter support). Also, :ghc-flag:`-XTemplateHaskellQuotes` is - considered safe under Safe Haskell. - -- The ``__GLASGOW_HASKELL_TH__`` CPP constant denoting support for - :ghc-flag:`-XTemplateHaskell` introduced in GHC 7.10.1 has been changed to - use the values ``1``/``0`` instead of the previous ``YES``/``NO`` - values. - -- Partial type signatures can now be used in splices, see - :ref:`pts-where`. - -- Template Haskell now fully supports typed holes and quoting unbound - variables. This means it is now possible to use pattern splices nested - inside quotation brackets. - -- Template Haskell now supports the use of ``UInfixT`` in types to - resolve infix operator fixities, in the same vein as ``UInfixP`` and - ``UInfixE`` in patterns and expressions. ``ParensT`` and ``InfixT`` - have also been introduced, serving the same functions as their - pattern and expression counterparts. - -- Template Haskell has now explicit support for representing GADTs. Until - now GADTs were encoded using ``NormalC``, ``RecC`` (record syntax) and - ``ForallC`` constructors. Two new constructors - ``GadtC`` and ``RecGadtC`` - - are now supported during quoting, splicing and reification. - -- Primitive chars (e.g., ``[| 'a'# |]``) and primitive strings (e.g., - ``[| "abc"# |]``) can now be quoted with Template Haskell. The - ``Lit`` data type also has a new constructor, ``CharPrimL``, for - primitive char literals. - -- ``addTopDecls`` now accepts annotation pragmas. - -- Internally, the implementation of quasi-quotes has been unified with - that of normal Template Haskell splices. Under the previous - implementation, top-level declaration quasi-quotes did not cause a - break in the declaration groups, unlike splices of the form - ``$(...)``. This behavior has been preserved under the new - implementation, and is now recognized and documented in - :ref:`th-syntax`. - -- The ``Lift`` class is now derivable via the :ghc-flag:`-XDeriveLift` extension. See - :ref:`deriving-lift` for more information. - -- The ``FamilyD`` data constructor and ``FamFlavour`` data type have - been removed. Data families are now represented by ``DataFamilyD`` and - open type families are now represented by ``OpenTypeFamilyD`` instead - of ``FamilyD``. Common elements of ``OpenTypeFamilyD`` and - ``ClosedTypeFamilyD`` have been moved to ``TypeFamilyHead``. - -- The representation of ``data``, ``newtype``, ``data instance``, and - ``newtype instance`` declarations has been changed to allow for - multi-parameter type classes in the ``deriving`` clause. In particular, - ``dataD`` and ``newtypeD`` now take a ``CxtQ`` instead of a ``[Name]`` - for the list of derived classes. - -- ``isExtEnabled`` can now be used to determine whether a language extension - is enabled in the ``Q`` monad. Similarly, ``extsEnabled`` can be used to list - all enabled language extensions. - -- One can now reify the strictness information of a constructors' fields using - Template Haskell's ``reifyConStrictness`` function, which takes into account - whether flags such as :ghc-flag:`-XStrictData` or - :ghc-flag:`-funbox-strict-fields` are enabled. - -- Previously, quoting a type signature like ``a -> a`` would produce the - abstract syntax for ``forall a. a -> a``. This behavior remains, but it - is extended to kinds, too, meaning that ``Proxy a -> Proxy a`` becomes - ``forall k (a :: k). Proxy a -> Proxy a``. This change is not intentional, - but is forced by the fact that GHC has a hard time telling kinds apart - from types. The effect of this change is that round-tripping kind- - polymorphic types will now require :ghc-flag:`-XTypeInType`. - -Runtime system -~~~~~~~~~~~~~~ - -- We have a shiny new two-step memory allocator for 64-bit platforms (see - :ghc-ticket:`9706`). In addition to simplifying the runtime system's - implementation this may significantly improve garbage collector performance. - Note, however, that Haskell processes will have an apparent virtual memory - footprint of a terabyte or so. Don't worry though, most of this amount is merely - mapped but uncommitted address space which is not backed by physical memory. - -- Support for performance monitoring with PAPI has been dropped. - -- :rts-flag:`-maxN⟨x⟩ <-maxN>` flag added to complement :rts-flag:`-N`. It will - choose to use at most ⟨x⟩ capabilities, limited by the number of processors - as :rts-flag:`-N` is. - -- The runtime linker is no longer greedy and will load only the needed objects - from archives. This means particularly on Windows packages requiring e.g. C99 - support will now function properly. As part of this the RTS on Windows - no longer re-exports deprecated posix functions under the undeprecated names - (see :ghc-ticket:`11223`). - -Build system -~~~~~~~~~~~~ - -- TODO FIXME. - -Package system -~~~~~~~~~~~~~~ - -- TODO FIXME. - -hsc2hs -~~~~~~ - -- :command:`hsc2hs` now supports the ``#alignment`` macro, which can be used to - calculate the alignment of a struct in bytes. Previously, ``#alignment`` - had to be implemented manually via a ``#let`` directive, e.g., :: - - #let alignment t = "%lu", (unsigned long)offsetof(struct {char x__; t (y__); }, y__) - - As a result, if you have the above directive in your code, it will now emit - a warning when compiled with GHC 8.0. - - .. code-block:: none - - Module.hsc:24:0: warning: "hsc_alignment" redefined [enabled by default] - In file included from dist/build/Module_hsc_make.c:1:0: - /path/to/ghc/lib/template-hsc.h:88:0: note: this is the location of the previous definition - #define hsc_alignment(t...) \ - ^ - - To make your code free of warnings on GHC 8.0 and still support earlier - versions, surround the directive with a pragma checking for the right GHC - version. :: - - #if __GLASGOW_HASKELL__ < 800 - #let alignment t = "%lu", (unsigned long)offsetof(struct {char x__; t (y__); }, y__) - #endif - -Libraries ---------- - -array -~~~~~ - -- Version number XXXXX (was 0.5.0.0) - - -.. _lib-base: - -base -~~~~ - -See ``changelog.md`` in the ``base`` package for full release notes. - -- Version number 4.9.0.0 (was 4.7.0.0) - -- :base-ref:`GHC.Stack <GHC-Stack.html>` exports two new types ``SrcLoc`` and ``CallStack``. A - ``SrcLoc`` contains package, module, and file names, as well as start - and end positions. A ``CallStack`` is essentially a ``[(String, SrcLoc)]``, - sorted by most-recent call. - -- ``error`` and ``undefined`` will now report a partial stack-trace - using the new ``CallStack`` feature (and the :ghc-flag:`-prof` stack if - available). - -- A new function, ``interruptible``, was added to ``GHC.IO`` allowing - an ``IO`` action to be run such that it can be interrupted by an - asynchronous exception, even if exceptions are masked (except if - masked with ``interruptibleMask``). - - This was introduced to fix the behavior of ``allowInterrupt``, which - would previously incorrectly allow exceptions in uninterruptible - regions (see :ghc-ticket:`9516`). - -- Per-thread allocation counters (``setAllocationCounter`` and - ``getAllocationCounter``) and limits (``enableAllocationLimit``, - ``disableAllocationLimit`` are now available from ``System.Mem``. Previously - this functionality was only available from :base-ref:`GHC.Conc <GHC-Stack.html>`. - -- ``forever``, ``filterM``, ``mapAndUnzipM``, ``zipWithM``, ``zipWithM_``, - ``replicateM``, and ``replicateM`` were generalized from ``Monad`` to - ``Applicative``. If this causes performance regressions, try to make the - implementation of ``(*>)`` match that of ``(>>)``. - -- Add ``URec``, ``UAddr``, ``UChar``, ``UDouble``, ``UFloat``, ``UInt``, and ``UWord`` to - :base-ref:`GHC.Generics <GHC-Generics.html>` as part of making GHC generics - capable of handling unlifted types (:ghc-ticket:`10868`) - -- Expand ``Floating`` class to include operations that allow for better - precision: ``log1p``, ``expm1``, ``log1pexp`` and ``log1mexp``. These are not - available from ``Prelude``, but the full class is exported from ``Numeric``. - -- Add ``Data.List.NonEmpty`` and ``Data.Semigroup`` (to become - super-class of ``Monoid`` in the future). These modules were - provided by the ``semigroups`` package previously. (:ghc-ticket:`10365`) - -- The constraints of various functions in ``Control.Monad`` have been - generalized from ``Monad`` to ``Applicative`` including ``filterM``, - ``zipWithM`` and ``replicateM_`` (see :ghc-ticket:`10168`). - -- Add ``GHC.TypeLits.TypeError`` and ``ErrorMessage`` to allow users - to define custom compile-time error messages. (see :ref:`custom-errors` and - the original :ghc-wiki:`proposal <Proposal/CustomTypeErrors>`). - -- The datatypes in ``GHC.Generics`` now have ``Enum``, ``Bounded``, ``Ix``, - ``Functor``, ``Applicative``, ``Monad``, ``MonadFix``, ``MonadPlus``, ``MonadZip``, - ``Foldable``, ``Foldable``, ``Traversable``, ``Generic1``, and ``Data`` instances - as appropriate. (:ghc-ticket:`9043`) - -- The ``Generic`` instance for ``Proxy`` is now poly-kinded (see :ghc-ticket:`10775`) - -- The ``IsString`` instance for ``[Char]`` has been modified to eliminate - ambiguity arising from overloaded strings and functions like ``(++)``. - -- Move ``Const`` from ``Control.Applicative`` to its own module in - ``Data.Functor.Const``. (see :ghc-ticket:`11135`) - -- Enable ``PolyKinds`` in the ``Data.Functor.Const`` module to give ``Const`` - the kind ``* -> k -> *`` (see :ghc-ticket:`10039`). - -- Add the ``TypeError`` datatype to ``Control.Exception``, which represents the - error that is thrown when an expression fails to typecheck when run using - :ghc-flag:`-fdefer-type-errors`. (see :ghc-ticket:`10284`) - -binary -~~~~~~ - -- Version number XXXXX (was 0.7.1.0) - -bytestring -~~~~~~~~~~ - -- Version number XXXXX (was 0.10.4.0) - -Cabal -~~~~~ - -- Version number XXXXX (was 1.18.1.3) - -containers -~~~~~~~~~~ - -- Version number XXXXX (was 0.5.4.0) - -deepseq -~~~~~~~ - -- Version number XXXXX (was 1.3.0.2) - -directory -~~~~~~~~~ - -- Version number XXXXX (was 1.2.0.2) - -filepath -~~~~~~~~ - -- Version number XXXXX (was 1.3.0.2) - -ghc -~~~ - -- TODO FIXME. - -- The ``HsBang`` type has been removed in favour of ``HsSrcBang`` and - ``HsImplBang``. Data constructors now always carry around their - strictness annotations as the user wrote them, whether from an - imported module or not. - -- Moved ``startsVarSym``, ``startsVarId``, ``startsConSym``, ``startsConId``, - ``startsVarSymASCII``, and ``isVarSymChar`` from ``Lexeme`` to the - ``GHC.Lemexe`` module of the ``ghc-boot`` library. - -- Add ``isImport``, ``isDecl``, and ``isStmt`` functions. - -- The `mi_fix_fn` field of `ModIface` had its type changed from - ``OccName -> Fixity`` to ``OccName -> Maybe Fixity``, where a returned value - of ``Nothing`` indicates a cache miss. As a result, the types of - ``mkIfaceFixCache`` and ``emptyIfaceFixCache`` were also changed to have a - return type of ``Maybe Fixity``, and a new ``mi_fix :: OccName -> Fixity`` - function was introduced which invokes ``mi_fix_fn`` but returns - ``defaultFixity`` upon a cache miss. - -ghc-boot -~~~~~~~~ - -- This is an internal package. Use with caution. - -- This package was renamed from ``bin-package-db`` to reflect its new purpose - of containing intra-GHC functionality that needs to be shared across - multiple GHC boot libraries. - -- Added ``GHC.Lexeme``, which contains functions for determining if a - character can be the first letter of a variable or data constructor in - Haskell, as defined by GHC. (These functions were moved from ``Lexeme`` - in ``ghc``.) - -- Added ``GHC.LanguageExtensions`` which contains a type listing all - supported language extensions. - -ghc-prim -~~~~~~~~ - -- Version number XXXXX (was 0.3.1.0) - -haskell98 -~~~~~~~~~ - -- Version number XXXXX (was 2.0.0.3) - -haskell2010 -~~~~~~~~~~~ - -- Version number XXXXX (was 1.1.1.1) - -hoopl -~~~~~ - -- Version number XXXXX (was 3.10.0.0) - -hpc -~~~ - -- Version number XXXXX (was 0.6.0.1) - -integer-gmp -~~~~~~~~~~~ - -- Version number XXXXX (was 0.5.1.0) - -old-locale -~~~~~~~~~~ - -- Version number XXXXX (was 1.0.0.6) - -old-time -~~~~~~~~ - -- Version number XXXXX (was 1.1.0.2) - -process -~~~~~~~ - -- Version number XXXXX (was 1.2.0.0) - -template-haskell -~~~~~~~~~~~~~~~~ - -- Version number XXXXX (was 2.9.0.0) - -- The ``Lift`` type class for lifting values into Template Haskell - splices now has a default signature ``lift :: Data a => a -> Q Exp``, - which means that you do not have to provide an explicit - implementation of ``lift`` for types which have a ``Data`` instance. - To manually use this default implementation, you can use the - ``liftData`` function which is now exported from - ``Language.Haskell.TH.Syntax``. - -- ``Info``'s constructors no longer have ``Fixity`` fields. A - ``qReifyFixity`` function was added to the ``Quasi`` type class (as - well as the ``reifyFixity`` function, specialized for ``Q``) to allow - lookup of fixity information for any given ``Name``. - -time -~~~~ - -- Version number XXXXX (was 1.4.1) - -unix -~~~~ - -- Version number XXXXX (was 2.7.0.0) - -Win32 -~~~~~ - -- Version number XXXXX (was 2.3.0.1) - -Known bugs ----------- - -- TODO FIXME diff --git a/docs/users_guide/8.2.1-notes.rst b/docs/users_guide/8.2.1-notes.rst new file mode 100644 index 0000000000..957552b302 --- /dev/null +++ b/docs/users_guide/8.2.1-notes.rst @@ -0,0 +1,193 @@ +.. _release-8-2-1: + +Release notes for version 8.2.1 +=============================== + +The significant changes to the various parts of the compiler are listed +in the following sections. There have also been numerous bug fixes and +performance improvements over the 8.0 branch. + +Highlights +---------- + +The highlights since the 8.0 branch are: + +- TODO FIXME + +Full details +------------ + +Language +~~~~~~~~ + +- TODO FIXME. + +Compiler +~~~~~~~~ + +- TODO FIXME. + +GHCi +~~~~ + +- TODO FIXME. + +Template Haskell +~~~~~~~~~~~~~~~~ + +- TODO FIXME. + +Runtime system +~~~~~~~~~~~~~~ + +- TODO FIXME. + +Build system +~~~~~~~~~~~~ + +- TODO FIXME. + +Package system +~~~~~~~~~~~~~~ + +- TODO FIXME. + +hsc2hs +~~~~~~ + +- TODO FIXME. + +Libraries +--------- + +array +~~~~~ + +- Version number XXXXX (was 0.5.0.0) + + +.. _lib-base: + +base +~~~~ + +See ``changelog.md`` in the ``base`` package for full release notes. + +- Version number 4.10.0.0 (was 4.9.0.0) + +binary +~~~~~~ + +- Version number XXXXX (was 0.7.1.0) + +bytestring +~~~~~~~~~~ + +- Version number XXXXX (was 0.10.4.0) + +Cabal +~~~~~ + +- Version number XXXXX (was 1.18.1.3) + +containers +~~~~~~~~~~ + +- Version number XXXXX (was 0.5.4.0) + +deepseq +~~~~~~~ + +- Version number XXXXX (was 1.3.0.2) + +directory +~~~~~~~~~ + +- Version number XXXXX (was 1.2.0.2) + +filepath +~~~~~~~~ + +- Version number XXXXX (was 1.3.0.2) + +ghc +~~~ + +- TODO FIXME. + +ghc-boot +~~~~~~~~ + +- This is an internal package. Use with caution. + +- TODO FIXME. + +ghc-prim +~~~~~~~~ + +- Version number XXXXX (was 0.3.1.0) + +haskell98 +~~~~~~~~~ + +- Version number XXXXX (was 2.0.0.3) + +haskell2010 +~~~~~~~~~~~ + +- Version number XXXXX (was 1.1.1.1) + +hoopl +~~~~~ + +- Version number XXXXX (was 3.10.0.0) + +hpc +~~~ + +- Version number XXXXX (was 0.6.0.1) + +integer-gmp +~~~~~~~~~~~ + +- Version number XXXXX (was 0.5.1.0) + +old-locale +~~~~~~~~~~ + +- Version number XXXXX (was 1.0.0.6) + +old-time +~~~~~~~~ + +- Version number XXXXX (was 1.1.0.2) + +process +~~~~~~~ + +- Version number XXXXX (was 1.2.0.0) + +template-haskell +~~~~~~~~~~~~~~~~ + +- Version number XXXXX (was 2.9.0.0) + +time +~~~~ + +- Version number XXXXX (was 1.4.1) + +unix +~~~~ + +- Version number XXXXX (was 2.7.0.0) + +Win32 +~~~~~ + +- Version number XXXXX (was 2.3.0.1) + +Known bugs +---------- + +- TODO FIXME diff --git a/docs/users_guide/index.rst b/docs/users_guide/index.rst index 60f8c9ad68..b7ff4c091e 100644 --- a/docs/users_guide/index.rst +++ b/docs/users_guide/index.rst @@ -12,7 +12,7 @@ Contents: license intro - 8.0.1-notes + 8.2.1-notes ghci runghc usage |