Struct lignin::callback_registry::CallbackRef

pub struct CallbackRef<S, C> where
    S: ThreadSafety,
    C: CallbackSignature,  { /* fields omitted */ }

Vdom A callback reference linked to a CallbackRegistration.

Implementations

impl<S: ThreadSafety, C> CallbackRef<S, C> where
    C: CallbackSignature, 

#[must_use]

pub fn deanonymize(self) -> Self

👎 Deprecated:

Call of .deanonymize() on named type.

When called on an opaque type, deanonymizes it into the underlying named type.

Both AutoSafe and Deanonymize must be in scope and the method must be called without qualification for this to work.

Calling this method on a named type returns the value and type unchanged and produces a deprecation warning.

impl<C> CallbackRef<ThreadSafe, C> where
    C: CallbackSignature, 

#[must_use]

pub fn prefer_thread_safe(self) -> Self

Gently nudges the compiler to choose the ThreadSafe version of a value if both are possible.

This method is by value, so it will resolve with higher priority than the by-reference method on the ThreadBound type.

Note that not all tooling will show the correct overload here, but the compiler knows which to pick.

#[must_use]

pub fn prefer_thread_safe_ref(&self) -> &Self

Gently nudges the compiler to choose the ThreadSafe version of a reference if both are possible.

This method is once by single reference, so it will resolve with higher priority than the twice-by-reference method on the ThreadBound type.

Note that not all tooling will show the correct overload here, but the compiler knows which to pick.

impl<C> CallbackRef<ThreadBound, C> where
    C: CallbackSignature, 

#[must_use]

pub fn prefer_thread_safe(&self) -> Self

Gently nudges the compiler to choose the ThreadSafe version of a value if both are is possible.

This method is by reference, so it will resolve with lower priority than the by-value method on the ThreadSafe type.

Note that not all tooling will show the correct overload here, but the compiler knows which to pick.

#[must_use]

pub fn prefer_thread_safe_ref<'b>(self: &&'b Self) -> &'b Self

Gently nudges the compiler to choose the ThreadSafe version of a reference if both are is possible.

This method is twice by reference, so it will resolve with lower priority than the once-by-reference method on the ThreadSafe type.

Note that not all tooling will show the correct overload here, but the compiler knows which to pick.

impl<S> CallbackRef<S, fn(event: Event)> where
    S: ThreadSafety, 

Separate impls due to Rust language limitation. See CallbackSignature and expect future broadening.

pub fn call(self, parameter: Event)

Invokes the stored handler with the stored receiver and parameter, provided that the original CallbackRegistration hasn’t been dropped yet.

impl<S, T> CallbackRef<S, fn(dom_ref: DomRef<&T>)> where
    S: ThreadSafety, 

Separate impls due to Rust language limitation. See CallbackSignature and expect future broadening.

pub fn call(self, parameter: DomRef<&T>)

Invokes the stored handler with the stored receiver and parameter, provided that the original CallbackRegistration hasn’t been dropped yet.

impl<S, C: ?Sized> CallbackRef<S, C> where
    S: ThreadSafety,
    C: CallbackSignature, 

These functions are intended as storage optimization for in-browser renderers.

The CallbackRef’s raw numerical value can be passed through JavaScript directly, rather than adding another layer of indirection.

Only available with the "callbacks" feature.

Most DOM renderers will still require an event listener table in order to unsubscribe from events.

Example

use js_sys::Function;
use lignin::{CallbackRef, ThreadBound, web};
use wasm_bindgen::{closure::Closure, JsCast, JsValue, UnwrapThrowExt};

let element: web_sys::Element = // …
let callback_ref: CallbackRef<ThreadBound, fn(web::Event)> = // …

let common_handler = Closure::<dyn Fn(JsValue, web_sys::Event)>::wrap(
  Box::new(|callback_ref: JsValue, event: web_sys::Event| {
    unsafe { CallbackRef::<ThreadBound, fn(web::Event)>::from_js(&callback_ref) }
    .expect_throw("Invalid `CallbackRef`.")
    .call(event.into());
  })
);

let listener = common_handler.as_ref().unchecked_ref::<Function>()
  .bind1(&JsValue::UNDEFINED, &callback_ref.into_js());

// `common_handler` must be either leaked or stored somewhere,
// since otherwise it will throw when called from JavaScript.

let result = element.add_event_listener_with_callback("click", &listener);

#[must_use]

pub fn into_js(self) -> JsValue

Returns this CallbackRef’s identity as JsValue, which can then for example be bound to a generic event handler shim.

Implementation Contract

The return value of this function must be treated as opaque handle.

#[must_use]

pub unsafe fn from_js(key: &JsValue) -> Option<Self>

Reconstructs a CallbackRef that was previously converted into a JsValue.

Safety

• key must have been retrieved verbatim from [.into_js],
• S must be compatible (i.e. the same or ThreadBound),
• if the original S was ThreadBound, the CallbackRef must be reconstructed on the same thread and
• C must be the same except for lifetime changes that would be okay in an assignment.

Trait Implementations

impl<S1, S2, C> Align<CallbackRef<S2, C>> for CallbackRef<S1, C> where
    C: CallbackSignature,
    S1: ThreadSafety + Into<S2>,
    S2: ThreadSafety, 

fn align(self) -> T

Contextually thread-binds an instance, or not. Use only without qualification.

fn align_ref(&self) -> &T

Contextually thread-binds a reference, or not. Use only without qualification.

impl<S, C> Clone for CallbackRef<S, C> where
    S: ThreadSafety,
    C: CallbackSignature, 

fn clone(&self) -> Self

Returns a copy of the value.

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

Performs copy-assignment from source.

impl<S, C> Copy for CallbackRef<S, C> where
    S: ThreadSafety,
    C: CallbackSignature, 

impl<C, O> Deanonymize<CallbackRef<ThreadSafe, C>> for O where
    C: CallbackSignature,
    O: Send + Sync + AutoSafe<CallbackRef<ThreadBound, C>>, 

#[must_use]

fn deanonymize(self) -> SafeVariant

Deanonymize towards a compatible concrete type.

impl<S, C> Debug for CallbackRef<S, C> where
    S: ThreadSafety,
    C: CallbackSignature, 

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

Formats the value using the given formatter.

impl<S, C> Eq for CallbackRef<S, C> where
    S: ThreadSafety,
    C: CallbackSignature, 

impl<R, C> From<&'_ CallbackRegistration<R, C>> for CallbackRef<ThreadSafe, C> where
    R: Sync,
    C: CallbackSignature, 

fn from(registration: &CallbackRegistration<R, C>) -> Self

Performs the conversion.

impl<R, C> From<&'_ CallbackRegistration<R, C>> for CallbackRef<ThreadBound, C> where
    C: CallbackSignature, 

fn from(registration: &CallbackRegistration<R, C>) -> Self

Performs the conversion.

impl<C> From<CallbackRef<ThreadSafe, C>> for CallbackRef<ThreadBound, C> where
    C: CallbackSignature, 

fn from(thread_safe: CallbackRef<ThreadSafe, C>) -> Self

Performs the conversion.

impl<S, C> Hash for CallbackRef<S, C> where
    S: ThreadSafety,
    C: CallbackSignature, 

fn hash<H: Hasher>(&self, state: &mut H)

Feeds this value into the given Hasher.

pub fn hash_slice<H>(data: &[Self], state: &mut H) where
    H: Hasher, 

Feeds a slice of this type into the given Hasher.

impl<S, C> Ord for CallbackRef<S, C> where
    S: ThreadSafety,
    C: CallbackSignature, 

fn cmp(&self, other: &Self) -> Ordering

This method returns an Ordering between self and other.

#[must_use]

pub fn max(self, other: Self) -> Self

Compares and returns the maximum of two values.

#[must_use]

pub fn min(self, other: Self) -> Self

Compares and returns the minimum of two values.

#[must_use]

pub fn clamp(self, min: Self, max: Self) -> Self

Restrict a value to a certain interval.

impl<S1, S2, C> PartialEq<CallbackRef<S2, C>> for CallbackRef<S1, C> where
    S1: ThreadSafety,
    S2: ThreadSafety,
    C: CallbackSignature, 

fn eq(&self, other: &CallbackRef<S2, C>) -> bool

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

#[must_use]

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

This method tests for !=.

impl<S1, S2, C> PartialOrd<CallbackRef<S2, C>> for CallbackRef<S1, C> where
    S1: ThreadSafety,
    S2: ThreadSafety,
    C: CallbackSignature, 

fn partial_cmp(&self, other: &CallbackRef<S2, C>) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

#[must_use]

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

This method tests less than (for self and other) and is used by the < operator.

#[must_use]

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

This method tests less than or equal to (for self and other) and is used by the <= operator.

#[must_use]

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

This method tests greater than (for self and other) and is used by the > operator.

#[must_use]

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

This method tests greater than or equal to (for self and other) and is used by the >= operator.

impl<S, C> Vdom for CallbackRef<S, C> where
    S: ThreadSafety,
    C: CallbackSignature, 

type ThreadSafety = S

The ThreadSafety of the Vdom type, either ThreadSafe or ThreadBound.