State<S, A> class final

State<S, A> is used to store, update, and extract state in a functional way.

S is a State (e.g. the current State of your Bank Account). A is value that you extract out of the State (Account Balance fetched from the current state of your Bank Account S).

Inheritance

Object
HKT2<_StateHKT, S, A>
State

Mixed-in types

Functor2<_StateHKT, S, A>
Applicative2<_StateHKT, S, A>
Monad2<_StateHKT, S, A>

Constructors

State((A, S) _run(S state)): Build a new State given a (A, S) Function(S).
const
State.flatten(State<S, State<S, A>> state): Flat a State contained inside another State to be a single State.
factory

Properties

hashCode → int: The hash code for this object.
no setteroverride
runtimeType → Type: A representation of the runtime type of the object.
no setterinherited

Methods

andThen<C>(covariant State<S, C> then()) → State<S, C>: Chain the result of then to this State.
override
ap<C>(covariant State<S, C Function(A a)> a) → State<S, C>: Apply the function contained inside a to change the value of type A to a value of type C.
override
call<C>(covariant State<S, C> state) → State<S, C>: Chain multiple functions having the same state S.
override
chainFirst<C>(covariant State<S, C> chain(A a)) → State<S, A>: Chain a request that returns another State, execute it, ignore the result, and return the same value as the current State.
override
evaluate(S state) → A: Execute run and extract the value A.
execute(S state) → S: Execute run and extract the state S.
flatMap<C>(covariant State<S, C> f(A a)) → State<S, C>: Used to chain multiple functions that return a State.
override
get() → State<S, S>: Extract the current state S.
gets(A f(S state)) → State<S, A>: Change the value getter based on the current state S.
map<C>(C f(A a)) → State<S, C>: Change the value inside State<S, A> from type A to type C using f.
override
map2<C, D>(covariant State<S, C> m1, D f(A a, C c)) → State<S, D>: Change type of this State based on its value of type A and the value of type C of another State.
override
map3<C, D, E>(covariant State<S, C> m1, covariant State<S, D> m2, E f(A a, C c, D d)) → State<S, E>: Change type of this State based on its value of type A, the value of type C of a second State, and the value of type D of a third State.
override
modify(S f(S state)) → State<S, Unit>: Change the current state S using f and return nothing (Unit).
noSuchMethod(Invocation invocation) → dynamic: Invoked when a nonexistent method or property is accessed.
inherited
pure<C>(C c) → State<S, C>: Return a State<S, C> containing c as value.
override
put(S state) → State<S, Unit>: Set a new state and return nothing (Unit).
run(S state) → (A, S): Extract value A and state S by passing the original state S.
toStateAsync() → StateAsync<S, A>: Lift a sync State to an async StateAsync.
toString() → String: A string representation of this object.
inherited

Operators

operator ==(Object other) → bool: The equality operator.
override

Static Methods

sequenceList<S, A>(List<State<S, A>> list) → State<S, List<A>>: Convert a List<State<S, A>> to a single State<S, List<A>>.
traverseList<S, A, B>(List<A> list, State<S, B> f(A a)) → State<S, List<B>>: Map each element in the list to a State using the function f, and collect the result in a State<S, List<B>>.
traverseListWithIndex<S, A, B>(List<A> list, State<S, B> f(A a, int i)) → State<S, List<B>>: Map each element in the list to a State using the function f, and collect the result in a State<S, List<B>>.