This package allows you to write warning-free code
that compiles with versions of base
before and after AMP and FTP,
that is, base
before and beginning with 4.8, respectively,
and GHC before and beginning with 7.10, respectively.
It serves three purposes:
Prevent you from name clashes of FTP-Prelude
with locally defined functions having names like <*>
, join
, foldMap
.
Prevent you from redundant import warnings
if you manually import Data.Monoid
or Control.Applicative
.
Fix list functions to the list type, contrarily to the aim of the FTP.
This way you are saved from length (2,1) == 1
and maximum (2,1) == 1
,
until you import Data.Foldable
.
You should add
import Prelude2010
import Prelude ()
to your modules.
This way, you must change all affected modules.
If you want to avoid this you may try the prelude2010
package
or if you already import Prelude explicitly, you may try to add
Default-Extensions: CPP, NoImplicitPrelude
CPP-Options: -DPrelude=Prelude2010
to your Cabal file.
In my opinion, this is the wrong way round.
The presented Prelude2010 module should have been the one for GHC-7.10
and the Prelude with added and generalized list functions
should have been an additional PreludeFTP,
preferably exported by a separate package
like all other alternate Prelude projects.
But the purpose of the FTP was to save some import statements
at the expense of blowing up the Foldable
class
and prevent simple ways to write code that works
with GHC version before and starting with GHC-7.10
and that does not provoke warnings.
Related packages:
'base-compat': The opposite approach -
Make future function definitions available in older GHC versions.
haskell2010
: Defines the Prelude for Haskell 2010.
Unfortunately, haskell2010
is not available anymore since GHC-7.10,
because of the AMP.
'numeric-prelude':
It is intended to provide a refined numeric class hierarchy
but it also provides a non-numeric subset of the Prelude
that is more stable than the one of base
.