hxt-9.1.6: A collection of tools for processing XML with Haskell.

Data.Function.Selector

Synopsis

- data Selector s a = S {
  - getS :: s -> a
  - setS :: a -> s -> s
  }
- chgS :: Selector s a -> (a -> a) -> s -> s
- chgM :: Monad m => Selector s a -> (a -> m a) -> s -> m s
- mkSelector :: (s -> a) -> (a -> s -> s) -> Selector s a
- idS :: Selector s s
- (.&&&.) :: Selector s a -> Selector s b -> Selector s (a, b)
- class Comp1 s a | s -> a where
  - comp1 :: Selector s a
- class Comp2 s a | s -> a where
  - comp2 :: Selector s a
- class Comp3 s a | s -> a where
  - comp3 :: Selector s a

# Documentation

data Selector s a

A Selector is a pair of an access function and a modifying function for reading and updating parts of a composite type

Constructors

S |

Fields

getS :: s -> a
setS :: a -> s -> s

Instances

Category Selector |

chgS :: Selector s a -> (a -> a) -> s -> s

chgM :: Monad m => Selector s a -> (a -> m a) -> s -> m s

mkSelector :: (s -> a) -> (a -> s -> s) -> Selector s a

Alias for constructor S

idS :: Selector s s

(.&&&.) :: Selector s a -> Selector s b -> Selector s (a, b)

class Comp1 s a | s -> a where

Selectors for pairs and 3-tuples: comp1, comp2, comp3, this can be extended to n-tuples

Methods

comp1 :: Selector s a

Instances

Comp1 (a, b) a |
Comp1 (a, b, c) a |

class Comp2 s a | s -> a where

Methods

comp2 :: Selector s a

Instances

Comp2 (a, b) b |
Comp2 (a, b, c) b |

class Comp3 s a | s -> a where

Methods

comp3 :: Selector s a

Instances

Comp3 (a, b, c) c |