Text.XML.PolySoup.Predicate

A generic extracting predicate.

Documentation

newtype Q a b

A predicate checks if the given element satisfies some properties and extracts its attribute values. You can compose predicates using Functor, Applicative and Alternative operators: *>, <*, <|> etc. Note, that it doesn't really have sense to use function like many or some, since the extracting predicate doesn't consume any input.

Constructors

Q

Fields

• runQ :: a -> Maybe b

Instances

Functor (Q a)

Methods

fmap :: (a -> b) -> Q a a -> Q a b

(<$) :: a -> Q a b -> Q a a

Applicative (Q a)

Methods

pure :: a -> Q a a

(<*>) :: Q a (a -> b) -> Q a a -> Q a b

(*>) :: Q a a -> Q a b -> Q a b

(<*) :: Q a a -> Q a b -> Q a a

Alternative (Q a)

Methods

empty :: Q a a

(<|>) :: Q a a -> Q a a -> Q a a

some :: Q a a -> Q a [a]

many :: Q a a -> Q a [a]

true :: Q a a

Predicate which is always satisfied.

satisfy :: (a -> Bool) -> Q a a

Check if the given predicate is satisfied.