Struct SimpleCell

Source
pub struct SimpleCell<T: ?Sized>(/* private fields */);
Expand description

Just a wrapper around Rc<RefCell> to make using it a bit cleaner.

Implementations§

Source§

impl<T> SimpleCell<T>

Source

pub fn new(value: T) -> Self

Source

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

Source

pub fn try_unwrap(self) -> Result<T, SimpleCell<T>>

Source

pub fn replace_with<F>(&self, f: F) -> T
where F: FnOnce(&mut T) -> T,

Source

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

Source

pub fn get(&self) -> Ref<'_, T>

Source

pub fn try_get(&self) -> Result<Ref<'_, T>, BorrowError>

Source

pub fn get_mut(&self) -> RefMut<'_, T>

Source

pub fn try_get_mut(&self) -> Result<RefMut<'_, T>, BorrowMutError>

Source

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

Source

pub fn clone(&self) -> Self

Source§

impl<T: Default> SimpleCell<T>

Source

pub fn take(&self) -> T

Methods from Deref<Target = RefCell<T>>§

1.24.0 · Source

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

Replaces the wrapped value with a new one, returning the old value, without deinitializing either one.

This function corresponds to std::mem::replace.

§Panics

Panics if the value is currently borrowed.

§Examples
use std::cell::RefCell;
let cell = RefCell::new(5);
let old_value = cell.replace(6);
assert_eq!(old_value, 5);
assert_eq!(cell, RefCell::new(6));
1.35.0 · Source

pub fn replace_with<F>(&self, f: F) -> T
where F: FnOnce(&mut T) -> T,

Replaces the wrapped value with a new one computed from f, returning the old value, without deinitializing either one.

§Panics

Panics if the value is currently borrowed.

§Examples
use std::cell::RefCell;
let cell = RefCell::new(5);
let old_value = cell.replace_with(|&mut old| old + 1);
assert_eq!(old_value, 5);
assert_eq!(cell, RefCell::new(6));
1.24.0 · Source

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

Swaps the wrapped value of self with the wrapped value of other, without deinitializing either one.

This function corresponds to std::mem::swap.

§Panics

Panics if the value in either RefCell is currently borrowed, or if self and other point to the same RefCell.

§Examples
use std::cell::RefCell;
let c = RefCell::new(5);
let d = RefCell::new(6);
c.swap(&d);
assert_eq!(c, RefCell::new(6));
assert_eq!(d, RefCell::new(5));
1.0.0 · Source

pub fn borrow(&self) -> Ref<'_, T>

Immutably borrows the wrapped value.

The borrow lasts until the returned Ref exits scope. Multiple immutable borrows can be taken out at the same time.

§Panics

Panics if the value is currently mutably borrowed. For a non-panicking variant, use try_borrow.

§Examples
use std::cell::RefCell;

let c = RefCell::new(5);

let borrowed_five = c.borrow();
let borrowed_five2 = c.borrow();

An example of panic:

use std::cell::RefCell;

let c = RefCell::new(5);

let m = c.borrow_mut();
let b = c.borrow(); // this causes a panic
1.13.0 · Source

pub fn try_borrow(&self) -> Result<Ref<'_, T>, BorrowError>

Immutably borrows the wrapped value, returning an error if the value is currently mutably borrowed.

The borrow lasts until the returned Ref exits scope. Multiple immutable borrows can be taken out at the same time.

This is the non-panicking variant of borrow.

§Examples
use std::cell::RefCell;

let c = RefCell::new(5);

{
    let m = c.borrow_mut();
    assert!(c.try_borrow().is_err());
}

{
    let m = c.borrow();
    assert!(c.try_borrow().is_ok());
}
1.0.0 · Source

pub fn borrow_mut(&self) -> RefMut<'_, T>

Mutably borrows the wrapped value.

The borrow lasts until the returned RefMut or all RefMuts derived from it exit scope. The value cannot be borrowed while this borrow is active.

§Panics

Panics if the value is currently borrowed. For a non-panicking variant, use try_borrow_mut.

§Examples
use std::cell::RefCell;

let c = RefCell::new("hello".to_owned());

*c.borrow_mut() = "bonjour".to_owned();

assert_eq!(&*c.borrow(), "bonjour");

An example of panic:

use std::cell::RefCell;

let c = RefCell::new(5);
let m = c.borrow();

let b = c.borrow_mut(); // this causes a panic
1.13.0 · Source

pub fn try_borrow_mut(&self) -> Result<RefMut<'_, T>, BorrowMutError>

Mutably borrows the wrapped value, returning an error if the value is currently borrowed.

The borrow lasts until the returned RefMut or all RefMuts derived from it exit scope. The value cannot be borrowed while this borrow is active.

This is the non-panicking variant of borrow_mut.

§Examples
use std::cell::RefCell;

let c = RefCell::new(5);

{
    let m = c.borrow();
    assert!(c.try_borrow_mut().is_err());
}

assert!(c.try_borrow_mut().is_ok());
1.12.0 · Source

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

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

§Examples
use std::cell::RefCell;

let c = RefCell::new(5);

let ptr = c.as_ptr();
1.37.0 · Source

pub unsafe fn try_borrow_unguarded(&self) -> Result<&T, BorrowError>

Immutably borrows the wrapped value, returning an error if the value is currently mutably borrowed.

§Safety

Unlike RefCell::borrow, this method is unsafe because it does not return a Ref, thus leaving the borrow flag untouched. Mutably borrowing the RefCell while the reference returned by this method is alive is undefined behavior.

§Examples
use std::cell::RefCell;

let c = RefCell::new(5);

{
    let m = c.borrow_mut();
    assert!(unsafe { c.try_borrow_unguarded() }.is_err());
}

{
    let m = c.borrow();
    assert!(unsafe { c.try_borrow_unguarded() }.is_ok());
}
1.50.0 · Source

pub fn take(&self) -> T

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

§Panics

Panics if the value is currently borrowed.

§Examples
use std::cell::RefCell;

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

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

Trait Implementations§

Source§

impl<T: Debug> Debug for SimpleCell<T>

Source§

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

Formats the value using the given formatter. Read more
Source§

impl<T: Default> Default for SimpleCell<T>

Source§

fn default() -> Self

Returns the “default value” for a type. Read more
Source§

impl<T> Deref for SimpleCell<T>

Source§

type Target = RefCell<T>

The resulting type after dereferencing.
Source§

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

Dereferences the value.
Source§

impl<T> From<T> for SimpleCell<T>

Source§

fn from(t: T) -> Self

Converts to this type from the input type.
Source§

impl<T: PartialEq + ?Sized> PartialEq for SimpleCell<T>

Source§

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

Tests for self and other values to be equal, and is used by ==.
1.0.0 · Source§

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

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.
Source§

impl<T: Eq> Eq for SimpleCell<T>

Auto Trait Implementations§

§

impl<T> Freeze for SimpleCell<T>
where T: ?Sized,

§

impl<T> !RefUnwindSafe for SimpleCell<T>

§

impl<T> !Send for SimpleCell<T>

§

impl<T> !Sync for SimpleCell<T>

§

impl<T> Unpin for SimpleCell<T>
where T: ?Sized,

§

impl<T> !UnwindSafe for SimpleCell<T>

Blanket Implementations§

Source§

impl<T> Any for T
where T: 'static + ?Sized,

Source§

fn type_id(&self) -> TypeId

Gets the TypeId of self. Read more
Source§

impl<T> Borrow<T> for T
where T: ?Sized,

Source§

fn borrow(&self) -> &T

Immutably borrows from an owned value. Read more
Source§

impl<T> BorrowMut<T> for T
where T: ?Sized,

Source§

fn borrow_mut(&mut self) -> &mut T

Mutably borrows from an owned value. Read more
Source§

impl<T> From<!> for T

Source§

fn from(t: !) -> T

Converts to this type from the input type.
Source§

impl<T> From<T> for T

Source§

fn from(t: T) -> T

Returns the argument unchanged.

Source§

impl<T, U> Into<U> for T
where U: From<T>,

Source§

fn into(self) -> U

Calls U::from(self).

That is, this conversion is whatever the implementation of From<T> for U chooses to do.

Source§

impl<T> IntoEither for T

Source§

fn into_either(self, into_left: bool) -> Either<Self, Self>

Converts self into a Left variant of Either<Self, Self> if into_left is true. Converts self into a Right variant of Either<Self, Self> otherwise. Read more
Source§

fn into_either_with<F>(self, into_left: F) -> Either<Self, Self>
where F: FnOnce(&Self) -> bool,

Converts self into a Left variant of Either<Self, Self> if into_left(&self) returns true. Converts self into a Right variant of Either<Self, Self> otherwise. Read more
Source§

impl<T> Pointable for T

Source§

const ALIGN: usize

The alignment of pointer.
Source§

type Init = T

The type for initializers.
Source§

unsafe fn init(init: <T as Pointable>::Init) -> usize

Initializes a with the given initializer. Read more
Source§

unsafe fn deref<'a>(ptr: usize) -> &'a T

Dereferences the given pointer. Read more
Source§

unsafe fn deref_mut<'a>(ptr: usize) -> &'a mut T

Mutably dereferences the given pointer. Read more
Source§

unsafe fn drop(ptr: usize)

Drops the object pointed to by the given pointer. Read more
Source§

impl<P, T> Receiver for P
where P: Deref<Target = T> + ?Sized, T: ?Sized,

Source§

type Target = T

🔬This is a nightly-only experimental API. (arbitrary_self_types)
The target type on which the method may be called.
Source§

impl<T, U> TryFrom<U> for T
where U: Into<T>,

Source§

type Error = Infallible

The type returned in the event of a conversion error.
Source§

fn try_from(value: U) -> Result<T, <T as TryFrom<U>>::Error>

Performs the conversion.
Source§

impl<T, U> TryInto<U> for T
where U: TryFrom<T>,

Source§

type Error = <U as TryFrom<T>>::Error

The type returned in the event of a conversion error.
Source§

fn try_into(self) -> Result<U, <U as TryFrom<T>>::Error>

Performs the conversion.
Source§

impl<V, T> VZip<V> for T
where V: MultiLane<T>,

Source§

fn vzip(self) -> V