| Copyright | (c) The University of Glasgow, CWI 2001--2004 |
|---|---|
| License | BSD-style (see the LICENSE file) |
| Maintainer | generics@haskell.org |
| Stability | experimental |
| Portability | non-portable (local universal quantification) |
| Safe Haskell | Safe |
| Language | Haskell98 |
Data.Generics.Aliases
Contents
Description
"Scrap your boilerplate" --- Generic programming in Haskell See http://www.cs.uu.nl/wiki/GenericProgramming/SYB. The present module provides a number of declarations for typical generic function types, corresponding type case, and others.
- mkT :: (Typeable a, Typeable b) => (b -> b) -> a -> a
- mkQ :: (Typeable a, Typeable b) => r -> (b -> r) -> a -> r
- mkM :: (Monad m, Typeable a, Typeable b) => (b -> m b) -> a -> m a
- mkMp :: (MonadPlus m, Typeable a, Typeable b) => (b -> m b) -> a -> m a
- mkR :: (MonadPlus m, Typeable a, Typeable b) => m b -> m a
- ext0 :: (Typeable a, Typeable b) => c a -> c b -> c a
- extT :: (Typeable a, Typeable b) => (a -> a) -> (b -> b) -> a -> a
- extQ :: (Typeable a, Typeable b) => (a -> q) -> (b -> q) -> a -> q
- extM :: (Monad m, Typeable a, Typeable b) => (a -> m a) -> (b -> m b) -> a -> m a
- extMp :: (MonadPlus m, Typeable a, Typeable b) => (a -> m a) -> (b -> m b) -> a -> m a
- extB :: (Typeable a, Typeable b) => a -> b -> a
- extR :: (Monad m, Typeable a, Typeable b) => m a -> m b -> m a
- type GenericT = forall a. Data a => a -> a
- type GenericQ r = forall a. Data a => a -> r
- type GenericM m = forall a. Data a => a -> m a
- type GenericB = forall a. Data a => a
- type GenericR m = forall a. Data a => m a
- type Generic c = forall a. Data a => a -> c a
- data Generic' c = Generic' {
- unGeneric' :: Generic c
- newtype GenericT' = GT {}
- newtype GenericQ' r = GQ {}
- newtype GenericM' m = GM {}
- orElse :: Maybe a -> Maybe a -> Maybe a
- recoverMp :: MonadPlus m => GenericM m -> GenericM m
- recoverQ :: MonadPlus m => r -> GenericQ (m r) -> GenericQ (m r)
- choiceMp :: MonadPlus m => GenericM m -> GenericM m -> GenericM m
- choiceQ :: MonadPlus m => GenericQ (m r) -> GenericQ (m r) -> GenericQ (m r)
- ext1 :: (Data a, Typeable t) => c a -> (forall d. Data d => c (t d)) -> c a
- ext1T :: (Data d, Typeable t) => (forall e. Data e => e -> e) -> (forall f. Data f => t f -> t f) -> d -> d
- ext1M :: (Monad m, Data d, Typeable t) => (forall e. Data e => e -> m e) -> (forall f. Data f => t f -> m (t f)) -> d -> m d
- ext1Q :: (Data d, Typeable t) => (d -> q) -> (forall e. Data e => t e -> q) -> d -> q
- ext1R :: (Monad m, Data d, Typeable t) => m d -> (forall e. Data e => m (t e)) -> m d
- ext1B :: (Data a, Typeable t) => a -> (forall b. Data b => t b) -> a
- ext2T :: (Data d, Typeable t) => (forall e. Data e => e -> e) -> (forall d1 d2. (Data d1, Data d2) => t d1 d2 -> t d1 d2) -> d -> d
- ext2M :: (Monad m, Data d, Typeable t) => (forall e. Data e => e -> m e) -> (forall d1 d2. (Data d1, Data d2) => t d1 d2 -> m (t d1 d2)) -> d -> m d
- ext2Q :: (Data d, Typeable t) => (d -> q) -> (forall d1 d2. (Data d1, Data d2) => t d1 d2 -> q) -> d -> q
- ext2R :: (Monad m, Data d, Typeable t) => m d -> (forall d1 d2. (Data d1, Data d2) => m (t d1 d2)) -> m d
- ext2B :: (Data a, Typeable t) => a -> (forall d1 d2. (Data d1, Data d2) => t d1 d2) -> a
Combinators to "make" generic functions via cast
mkT :: (Typeable a, Typeable b) => (b -> b) -> a -> a
Make a generic transformation; start from a type-specific case; preserve the term otherwise
mkQ :: (Typeable a, Typeable b) => r -> (b -> r) -> a -> r
Make a generic query; start from a type-specific case; return a constant otherwise
mkM :: (Monad m, Typeable a, Typeable b) => (b -> m b) -> a -> m a
Make a generic monadic transformation; start from a type-specific case; resort to return otherwise
mkMp :: (MonadPlus m, Typeable a, Typeable b) => (b -> m b) -> a -> m a
Make a generic monadic transformation for MonadPlus; use "const mzero" (i.e., failure) instead of return as default.
mkR :: (MonadPlus m, Typeable a, Typeable b) => m b -> m a
Make a generic builder; start from a type-specific ase; resort to no build (i.e., mzero) otherwise
extT :: (Typeable a, Typeable b) => (a -> a) -> (b -> b) -> a -> a
Extend a generic transformation by a type-specific case
extQ :: (Typeable a, Typeable b) => (a -> q) -> (b -> q) -> a -> q
Extend a generic query by a type-specific case
extM :: (Monad m, Typeable a, Typeable b) => (a -> m a) -> (b -> m b) -> a -> m a
Extend a generic monadic transformation by a type-specific case
extMp :: (MonadPlus m, Typeable a, Typeable b) => (a -> m a) -> (b -> m b) -> a -> m a
Extend a generic MonadPlus transformation by a type-specific case
Type synonyms for generic function types
type GenericT = forall a. Data a => a -> a
Generic transformations, i.e., take an "a" and return an "a"
type GenericQ r = forall a. Data a => a -> r
Generic queries of type "r", i.e., take any "a" and return an "r"
type GenericM m = forall a. Data a => a -> m a
Generic monadic transformations, i.e., take an "a" and compute an "a"
type GenericR m = forall a. Data a => m a
Generic readers, say monadic builders, i.e., produce an "a" with the help of a monad "m".
type Generic c = forall a. Data a => a -> c a
The general scheme underlying generic functions assumed by gfoldl; there are isomorphisms such as GenericT = Generic T.
data Generic' c
Wrapped generic functions; recall: [Generic c] would be legal but [Generic' c] not.
Constructors
| Generic' | |
Fields
| |
newtype GenericT'
Other first-class polymorphic wrappers
Ingredients of generic functions
Function combinators on generic functions
recoverMp :: MonadPlus m => GenericM m -> GenericM m
Recover from the failure of monadic transformation by identity
recoverQ :: MonadPlus m => r -> GenericQ (m r) -> GenericQ (m r)
Recover from the failure of monadic query by a constant
choiceQ :: MonadPlus m => GenericQ (m r) -> GenericQ (m r) -> GenericQ (m r)
Choice for monadic queries
Type extension for unary type constructors
ext1T :: (Data d, Typeable t) => (forall e. Data e => e -> e) -> (forall f. Data f => t f -> t f) -> d -> d
Type extension of transformations for unary type constructors
ext1M :: (Monad m, Data d, Typeable t) => (forall e. Data e => e -> m e) -> (forall f. Data f => t f -> m (t f)) -> d -> m d
Type extension of monadic transformations for type constructors
ext1Q :: (Data d, Typeable t) => (d -> q) -> (forall e. Data e => t e -> q) -> d -> q
Type extension of queries for type constructors
ext1R :: (Monad m, Data d, Typeable t) => m d -> (forall e. Data e => m (t e)) -> m d
Type extension of readers for type constructors
ext1B :: (Data a, Typeable t) => a -> (forall b. Data b => t b) -> a
Type extension of builders for type constructors
Type extension for binary type constructors
ext2T :: (Data d, Typeable t) => (forall e. Data e => e -> e) -> (forall d1 d2. (Data d1, Data d2) => t d1 d2 -> t d1 d2) -> d -> d
Type extension of transformations for unary type constructors
ext2M :: (Monad m, Data d, Typeable t) => (forall e. Data e => e -> m e) -> (forall d1 d2. (Data d1, Data d2) => t d1 d2 -> m (t d1 d2)) -> d -> m d
Type extension of monadic transformations for type constructors
ext2Q :: (Data d, Typeable t) => (d -> q) -> (forall d1 d2. (Data d1, Data d2) => t d1 d2 -> q) -> d -> q
Type extension of queries for type constructors