Trait freya::prelude::Readable

pub trait Readable {
    type Target: 'static + ?Sized;
    type Storage: AnyStorage;

    // Required methods
    fn try_read(
        &self
    ) -> Result<<Self::Storage as AnyStorage>::Ref<Self::Target>, BorrowError>;
    fn peek(&self) -> <Self::Storage as AnyStorage>::Ref<Self::Target>;

    // Provided methods
    fn map<O>(
        self,
        f: impl Fn(&Self::Target) -> &O + 'static
    ) -> MappedSignal<O, Self::Storage>
       where Self: Clone + Sized + 'static { ... }
    fn read(&self) -> <Self::Storage as AnyStorage>::Ref<Self::Target> { ... }
    fn cloned(&self) -> Self::Target
       where Self::Target: Clone { ... }
    fn with<O>(&self, f: impl FnOnce(&Self::Target) -> O) -> O { ... }
    fn with_peek<O>(&self, f: impl FnOnce(&Self::Target) -> O) -> O { ... }
    fn index<I>(
        &self,
        index: I
    ) -> <Self::Storage as AnyStorage>::Ref<<Self::Target as Index<I>>::Output>
       where Self::Target: Index<I> { ... }
}

A trait for states that can be read from like crate::Signal, crate::GlobalSignal, or crate::ReadOnlySignal. You may choose to accept this trait as a parameter instead of the concrete type to allow for more flexibility in your API. For example, instead of creating two functions, one that accepts a crate::Signal and one that accepts a crate::GlobalSignal, you can create one function that accepts a Readable type.

Required Associated Types

type Target: 'static + ?Sized

The target type of the reference.

type Storage: AnyStorage

The type of the storage this readable uses.

Required Methods

fn try_read( &self ) -> Result<<Self::Storage as AnyStorage>::Ref<Self::Target>, BorrowError>

Try to get the current value of the state. If this is a signal, this will subscribe the current scope to the signal. If the value has been dropped, this will panic.

fn peek(&self) -> <Self::Storage as AnyStorage>::Ref<Self::Target>

Get the current value of the state without subscribing to updates. If the value has been dropped, this will panic.

Provided Methods

fn map<O>( self, f: impl Fn(&Self::Target) -> &O + 'static ) -> MappedSignal<O, Self::Storage>

where Self: Clone + Sized + 'static,

Map the readable type to a new type.

fn read(&self) -> <Self::Storage as AnyStorage>::Ref<Self::Target>

Get the current value of the state. If this is a signal, this will subscribe the current scope to the signal. If the value has been dropped, this will panic.

fn cloned(&self) -> Self::Target

where Self::Target: Clone,

Clone the inner value and return it. If the value has been dropped, this will panic.

fn with<O>(&self, f: impl FnOnce(&Self::Target) -> O) -> O

Run a function with a reference to the value. If the value has been dropped, this will panic.

fn with_peek<O>(&self, f: impl FnOnce(&Self::Target) -> O) -> O

Run a function with a reference to the value. If the value has been dropped, this will panic.

fn index<I>( &self, index: I ) -> <Self::Storage as AnyStorage>::Ref<<Self::Target as Index<I>>::Output>

where Self::Target: Index<I>,

Index into the inner value and return a reference to the result. If the value has been dropped or the index is invalid, this will panic.

Object Safety

This trait is not object safe.

Implementors

impl<O, S> Readable for MappedSignal<O, S>

where S: AnyStorage, O: ?Sized,

type Target = O

type Storage = S

impl<T> Readable for GlobalMemo<T>

where T: PartialEq + 'static,

type Target = T

type Storage = UnsyncStorage

impl<T> Readable for GlobalSignal<T>

where T: 'static,

type Target = T

type Storage = UnsyncStorage

impl<T, S> Readable for CopyValue<T, S>

where T: 'static, S: Storage<T>,

type Target = T

type Storage = S

impl<T, S> Readable for ReadOnlySignal<T, S>

where S: Storage<SignalData<T>>,

type Target = T

type Storage = S

impl<T, S> Readable for Signal<T, S>

where S: Storage<SignalData<T>>,

type Target = T

type Storage = S