Copyright | (C) 2014-2016 Ryan Scott |
---|---|
License | BSD-style (see the file LICENSE) |
Maintainer | Ryan Scott |
Stability | Provisional |
Portability | GHC |
Safe Haskell | None |
Language | Haskell2010 |
Generic versions of TextShow
and TextShow1
class functions, as an alternative to
TextShow.TH, which uses Template Haskell. Because there is no Generic2
class, TextShow2
cannot be implemented generically.
This implementation is based off of the Generics.Deriving.Show
module from the
generic-deriving
library.
Since: 2
- genericShowt :: (Generic a, GTextShow (Rep a)) => a -> Text
- genericShowtl :: (Generic a, GTextShow (Rep a)) => a -> Text
- genericShowtPrec :: (Generic a, GTextShow (Rep a)) => Int -> a -> Text
- genericShowtlPrec :: (Generic a, GTextShow (Rep a)) => Int -> a -> Text
- genericShowtList :: (Generic a, GTextShow (Rep a)) => [a] -> Text
- genericShowtlList :: (Generic a, GTextShow (Rep a)) => [a] -> Text
- genericShowb :: (Generic a, GTextShow (Rep a)) => a -> Builder
- genericShowbPrec :: (Generic a, GTextShow (Rep a)) => Int -> a -> Builder
- genericShowbList :: (Generic a, GTextShow (Rep a)) => [a] -> Builder
- genericPrintT :: (Generic a, GTextShow (Rep a)) => a -> IO ()
- genericPrintTL :: (Generic a, GTextShow (Rep a)) => a -> IO ()
- genericHPrintT :: (Generic a, GTextShow (Rep a)) => Handle -> a -> IO ()
- genericHPrintTL :: (Generic a, GTextShow (Rep a)) => Handle -> a -> IO ()
- genericLiftShowbPrec :: (Generic1 f, GTextShow1 (Rep1 f)) => (Int -> a -> Builder) -> ([a] -> Builder) -> Int -> f a -> Builder
- genericShowbPrec1 :: (Generic a, Generic1 f, GTextShow (Rep a), GTextShow1 (Rep1 f)) => Int -> f a -> Builder
- class GTextShow f where
- gShowbPrec :: Int -> f a -> Builder
- class GTextShowCon f where
- gShowbPrecCon :: ConType -> Int -> f a -> Builder
- class GTextShow1 f where
- class GTextShow1Con f where
- class IsNullary f where
- data ConType
Generic show
functions
TextShow
instances can be easily defined for data types that are Generic
instances.
The easiest way to do this is to use the DeriveGeneric
extension.
{-# LANGUAGE DeriveGeneric #-} import GHC.Generics import TextShow import TextShow.Generic data D a = D a deriving (Generic, Generic1) instance TextShow a => TextShow (D a) where showbPrec =genericShowbPrec
instance TextShow1 D where liftShowbPrec =genericLiftShowbPrec
Understanding a compiler error
Suppose you intend to use genericShowbPrec
to define a TextShow
instance.
data Oops = Oops
-- forgot to add "deriving Generic" here!
instance TextShow Oops where
showbPrec = genericShowbPrec
If you forget to add a deriving
clause to your data type, at
compile-time, you will get an error message that begins roughly as follows:Generic
No instance for (GTextShow
(Rep Oops))
This error can be confusing, but don't let it intimidate you. The correct fix is
simply to add the missing "deriving
" clause.Generic
Similarly, if the compiler complains about not having an instance for (
, add a "GTextShow1
(Rep1 Oops1))deriving
" clause.Generic1
genericShowtPrec :: (Generic a, GTextShow (Rep a)) => Int -> a -> Text Source
A Generic
implementation of showPrect
.
Since: 2
genericShowtlPrec :: (Generic a, GTextShow (Rep a)) => Int -> a -> Text Source
A Generic
implementation of showtlPrec
.
Since: 2
genericShowtlList :: (Generic a, GTextShow (Rep a)) => [a] -> Text Source
A Generic
implementation of showtlList
.
Since: 2
genericPrintT :: (Generic a, GTextShow (Rep a)) => a -> IO () Source
A Generic
implementation of printT
.
Since: 2
genericPrintTL :: (Generic a, GTextShow (Rep a)) => a -> IO () Source
A Generic
implementation of printTL
.
Since: 2
genericHPrintT :: (Generic a, GTextShow (Rep a)) => Handle -> a -> IO () Source
A Generic
implementation of hPrintT
.
Since: 2
genericHPrintTL :: (Generic a, GTextShow (Rep a)) => Handle -> a -> IO () Source
A Generic
implementation of hPrintTL
.
Since: 2
genericLiftShowbPrec :: (Generic1 f, GTextShow1 (Rep1 f)) => (Int -> a -> Builder) -> ([a] -> Builder) -> Int -> f a -> Builder Source
A Generic1
implementation of genericLiftShowbPrec
.
Since: 2
genericShowbPrec1 :: (Generic a, Generic1 f, GTextShow (Rep a), GTextShow1 (Rep1 f)) => Int -> f a -> Builder Source
A 'Generic'/'Generic1' implementation of showbPrec1
.
Since: 2
The GTextShow
and GTextShow1
classes
class GTextShow f where Source
gShowbPrec :: Int -> f a -> Builder Source
This is used as the default generic implementation of showbPrec
.
class GTextShowCon f where Source
gShowbPrecCon :: ConType -> Int -> f a -> Builder Source
GTextShowCon * V1 Source | |
GTextShowCon * U1 Source | |
GTextShowCon * UChar Source | |
GTextShowCon * UDouble Source | |
GTextShowCon * UFloat Source | |
GTextShowCon * UInt Source | |
GTextShowCon * UWord Source | |
TextShow c => GTextShowCon * (K1 i c) Source | |
(GTextShowCon * f, GTextShowCon * g) => GTextShowCon * ((:*:) f g) Source | |
(Selector s, GTextShowCon * f) => GTextShowCon * (S1 s f) Source |
class GTextShow1 f where Source
Class of generic representation types (Rep1
) that can be converted to
a Builder
by lifting through a unary type constructor.
Since: 2
gLiftShowbPrec :: (Int -> a -> Builder) -> ([a] -> Builder) -> Int -> f a -> Builder Source
This is used as the default generic implementation of showbPrecWith
.
GTextShow1 V1 Source | |
(GTextShow1 f, GTextShow1 g) => GTextShow1 ((:+:) f g) Source | |
GTextShow1 f => GTextShow1 (D1 d f) Source | |
(Constructor c, GTextShow1Con f, IsNullary * f) => GTextShow1 (C1 c f) Source |
class GTextShow1Con f where Source
gLiftShowbPrecCon :: ConType -> (Int -> a -> Builder) -> ([a] -> Builder) -> Int -> f a -> Builder Source
GTextShow1Con U1 Source | |
GTextShow1Con Par1 Source | |
GTextShow1Con UChar Source | |
GTextShow1Con UDouble Source | |
GTextShow1Con UFloat Source | |
GTextShow1Con UInt Source | |
GTextShow1Con UWord Source | |
TextShow1 f => GTextShow1Con (Rec1 f) Source | |
TextShow c => GTextShow1Con (K1 i c) Source | |
(GTextShow1Con f, GTextShow1Con g) => GTextShow1Con ((:*:) f g) Source | |
(TextShow1 f, GTextShow1Con g) => GTextShow1Con ((:.:) f g) Source | |
(Selector s, GTextShow1Con f) => GTextShow1Con (S1 s f) Source |
class IsNullary f where Source
Class of generic representation types that represent a constructor with zero or more fields.
IsNullary * U1 Source | |
IsNullary * Par1 Source | |
IsNullary * UChar Source | |
IsNullary * UDouble Source | |
IsNullary * UFloat Source | |
IsNullary * UInt Source | |
IsNullary * UWord Source | |
IsNullary * (Rec1 f) Source | |
IsNullary * (K1 i c) Source | |
IsNullary * ((:*:) f g) Source | |
IsNullary * ((:.:) f g) Source | |
IsNullary * f => IsNullary * (S1 s f) Source |