Struct rquickjs::function::OnceFn

pub struct OnceFn<T>(pub Cell<Option<T>>);

Helper type for creating a function from a closure which implements FnMut

When called through [CellFn] will take the internal value leaving it empty. If the internal value was already empty it will return a error.

Tuple Fields

0: Cell<Option<T>>

Implementations

impl<T> OnceFn<T>

pub fn new(t: T) -> OnceFn<T>

Methods from Deref<Target = Cell<Option<F>>>

pub fn set(&self, val: T)

Sets the contained value.

Examples

use std::cell::Cell;

let c = Cell::new(5);

c.set(10);

pub fn swap(&self, other: &Cell<T>)

Swaps the values of two Cells. Difference with std::mem::swap is that this function doesn’t require &mut reference.

Examples

use std::cell::Cell;

let c1 = Cell::new(5i32);
let c2 = Cell::new(10i32);
c1.swap(&c2);
assert_eq!(10, c1.get());
assert_eq!(5, c2.get());

pub fn replace(&self, val: T) -> T

Replaces the contained value with val, and returns the old contained value.

Examples

use std::cell::Cell;

let cell = Cell::new(5);
assert_eq!(cell.get(), 5);
assert_eq!(cell.replace(10), 5);
assert_eq!(cell.get(), 10);

pub fn get(&self) -> T

Returns a copy of the contained value.

Examples

use std::cell::Cell;

let c = Cell::new(5);

let five = c.get();

pub fn update<F>(&self, f: F) -> Twhere F: FnOnce(T) -> T,

🔬This is a nightly-only experimental API. (cell_update)

Updates the contained value using a function and returns the new value.

Examples

#![feature(cell_update)]

use std::cell::Cell;

let c = Cell::new(5);
let new = c.update(|x| x + 1);

assert_eq!(new, 6);
assert_eq!(c.get(), 6);

pub fn as_ptr(&self) -> *mut T

Returns a raw pointer to the underlying data in this cell.

Examples

use std::cell::Cell;

let c = Cell::new(5);

let ptr = c.as_ptr();

pub fn take(&self) -> T

Takes the value of the cell, leaving Default::default() in its place.

Examples

use std::cell::Cell;

let c = Cell::new(5);
let five = c.take();

assert_eq!(five, 5);
assert_eq!(c.into_inner(), 0);

pub fn as_slice_of_cells(&self) -> &[Cell<T>]

Returns a &[Cell<T>] from a &Cell<[T]>

Examples

use std::cell::Cell;

let slice: &mut [i32] = &mut [1, 2, 3];
let cell_slice: &Cell<[i32]> = Cell::from_mut(slice);
let slice_cell: &[Cell<i32>] = cell_slice.as_slice_of_cells();

assert_eq!(slice_cell.len(), 3);

pub fn as_array_of_cells(&self) -> &[Cell<T>; N]

🔬This is a nightly-only experimental API. (as_array_of_cells)

Returns a &[Cell<T>; N] from a &Cell<[T; N]>

Examples

#![feature(as_array_of_cells)]
use std::cell::Cell;

let mut array: [i32; 3] = [1, 2, 3];
let cell_array: &Cell<[i32; 3]> = Cell::from_mut(&mut array);
let array_cell: &[Cell<i32>; 3] = cell_array.as_array_of_cells();

Trait Implementations

impl<F> AsRef<Cell<Option<F>>> for OnceFn<F>

fn as_ref(&self) -> &Cell<Option<F>>

Converts this type into a shared reference of the (usually inferred) input type.

impl<F> Deref for OnceFn<F>

type Target = Cell<Option<F>>

The resulting type after dereferencing.

fn deref(&self) -> &<OnceFn<F> as Deref>::Target

Dereferences the value.

impl<T> From<T> for OnceFn<T>

fn from(value: T) -> OnceFn<T>

Converts to this type from the input type.

impl<'js, R, Fun> IntoJsFunc<'js, ()> for OnceFn<Fun>where Fun: FnOnce() -> R + 'js, (): FromParams<'js> + 'js, R: IntoJs<'js> + 'js,

fn param_requirements() -> ParamRequirement

Returns the requirements this function has for the set of arguments used to call this function.

fn call(&self, params: Params<'_, 'js>) -> Result<Value<'js>, Error>

Call the function with the given parameters.

impl<'js, R, Fun, A> IntoJsFunc<'js, (A,)> for OnceFn<Fun>where Fun: FnOnce(A) -> R + 'js, (A,): FromParams<'js> + 'js, R: IntoJs<'js> + 'js,

fn param_requirements() -> ParamRequirement

Returns the requirements this function has for the set of arguments used to call this function.

fn call(&self, params: Params<'_, 'js>) -> Result<Value<'js>, Error>

Call the function with the given parameters.

impl<'js, R, Fun, A, B> IntoJsFunc<'js, (A, B)> for OnceFn<Fun>where Fun: FnOnce(A, B) -> R + 'js, (A, B): FromParams<'js> + 'js, R: IntoJs<'js> + 'js,

fn param_requirements() -> ParamRequirement

Returns the requirements this function has for the set of arguments used to call this function.

fn call(&self, params: Params<'_, 'js>) -> Result<Value<'js>, Error>

Call the function with the given parameters.

impl<'js, R, Fun, A, B, C> IntoJsFunc<'js, (A, B, C)> for OnceFn<Fun>where Fun: FnOnce(A, B, C) -> R + 'js, (A, B, C): FromParams<'js> + 'js, R: IntoJs<'js> + 'js,

fn param_requirements() -> ParamRequirement

Returns the requirements this function has for the set of arguments used to call this function.

fn call(&self, params: Params<'_, 'js>) -> Result<Value<'js>, Error>

Call the function with the given parameters.

impl<'js, R, Fun, A, B, C, D> IntoJsFunc<'js, (A, B, C, D)> for OnceFn<Fun>where Fun: FnOnce(A, B, C, D) -> R + 'js, (A, B, C, D): FromParams<'js> + 'js, R: IntoJs<'js> + 'js,

fn param_requirements() -> ParamRequirement

Returns the requirements this function has for the set of arguments used to call this function.

fn call(&self, params: Params<'_, 'js>) -> Result<Value<'js>, Error>

Call the function with the given parameters.

impl<'js, R, Fun, A, B, C, D, E> IntoJsFunc<'js, (A, B, C, D, E)> for OnceFn<Fun>where Fun: FnOnce(A, B, C, D, E) -> R + 'js, (A, B, C, D, E): FromParams<'js> + 'js, R: IntoJs<'js> + 'js,

fn param_requirements() -> ParamRequirement

Returns the requirements this function has for the set of arguments used to call this function.

fn call(&self, params: Params<'_, 'js>) -> Result<Value<'js>, Error>

Call the function with the given parameters.

impl<'js, R, Fun, A, B, C, D, E, F> IntoJsFunc<'js, (A, B, C, D, E, F)> for OnceFn<Fun>where Fun: FnOnce(A, B, C, D, E, F) -> R + 'js, (A, B, C, D, E, F): FromParams<'js> + 'js, R: IntoJs<'js> + 'js,

fn param_requirements() -> ParamRequirement

Returns the requirements this function has for the set of arguments used to call this function.

fn call(&self, params: Params<'_, 'js>) -> Result<Value<'js>, Error>

Call the function with the given parameters.

impl<'js, R, Fun, A, B, C, D, E, F, G> IntoJsFunc<'js, (A, B, C, D, E, F, G)> for OnceFn<Fun>where Fun: FnOnce(A, B, C, D, E, F, G) -> R + 'js, (A, B, C, D, E, F, G): FromParams<'js> + 'js, R: IntoJs<'js> + 'js,

fn param_requirements() -> ParamRequirement

Returns the requirements this function has for the set of arguments used to call this function.

fn call(&self, params: Params<'_, 'js>) -> Result<Value<'js>, Error>

Call the function with the given parameters.

impl<'js, R, Fun, A, B, C, D, E, F, G, H> IntoJsFunc<'js, (A, B, C, D, E, F, G, H)> for OnceFn<Fun>where Fun: FnOnce(A, B, C, D, E, F, G, H) -> R + 'js, (A, B, C, D, E, F, G, H): FromParams<'js> + 'js, R: IntoJs<'js> + 'js,

fn param_requirements() -> ParamRequirement

Returns the requirements this function has for the set of arguments used to call this function.

fn call(&self, params: Params<'_, 'js>) -> Result<Value<'js>, Error>

Call the function with the given parameters.