Struct freya::prelude::Memo

pub struct Memo<T>
where
    T: 'static,
{ /* private fields */ }

A value that is memoized. This is useful for caching the result of a computation.

Implementations

impl<T> Memo<T>

where T: 'static,

pub fn new(f: impl FnMut() -> T + 'static) -> Memo<T>

where T: PartialEq,

Create a new memo

pub fn origin_scope(&self) -> ScopeId

Get the scope that the signal was created in.

pub fn id(&self) -> GenerationalBoxId

Get the id of the signal.

Trait Implementations

impl<T> Clone for Memo<T>

where T: 'static,

fn clone(&self) -> Memo<T>

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl<T> Debug for Memo<T>

where T: Debug + 'static + PartialEq,

fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>

Formats the value using the given formatter.

impl<T> Deref for Memo<T>

where T: Clone + PartialEq,

type Target = dyn Fn() -> T

The resulting type after dereferencing.

fn deref(&self) -> &<Memo<T> as Deref>::Target

Dereferences the value.

impl<T> Display for Memo<T>

where T: Display + 'static + PartialEq,

fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>

Formats the value using the given formatter.

impl<T> From<Memo<T>> for ReadOnlySignal<T>

where T: PartialEq,

fn from(val: Memo<T>) -> ReadOnlySignal<T>

Converts to this type from the input type.

impl<T> IntoAttributeValue for Memo<T>

where T: Clone + IntoAttributeValue + PartialEq,

fn into_value(self) -> AttributeValue

Convert into an attribute value

impl<T> IntoDynNode for Memo<T>

where T: Clone + IntoDynNode + PartialEq,

fn into_dyn_node(self) -> DynamicNode

Consume this item along with a scopestate and produce a DynamicNode

impl<T> PartialEq<T> for Memo<T>

where T: PartialEq + 'static,

fn eq(&self, other: &T) -> bool

This method tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

This method tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl<T> PartialEq for Memo<T>

where T: 'static,

fn eq(&self, other: &Memo<T>) -> bool

This method tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

This method tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl<T> Readable for Memo<T>

where T: PartialEq,

fn peek_unchecked( &self ) -> <<Memo<T> as Readable>::Storage as AnyStorage>::Ref<'static, <Memo<T> as Readable>::Target>

Get the current value of the signal. Unlike read, this will not subscribe the current scope to the signal which can cause parts of your UI to not update.

If the signal has been dropped, this will panic.

type Target = T

The target type of the reference.

type Storage = UnsyncStorage

The type of the storage this readable uses.

fn try_read_unchecked( &self ) -> Result<<<Memo<T> as Readable>::Storage as AnyStorage>::Ref<'static, <Memo<T> as Readable>::Target>, BorrowError>

Try to get a reference to the value without checking the lifetime. This will subscribe the current scope to the signal.

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

where Self: Sized + Clone + '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. Calling this on a Signal is the same as using the signal() syntax to read and subscribe to its value

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.

fn read_unchecked( &self ) -> <Self::Storage as AnyStorage>::Ref<'static, Self::Target>

Get a reference to the value without checking the lifetime. This will subscribe the current scope to the signal.

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.

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.

impl<T> Copy for Memo<T>

where T: 'static,