# Struct once_cell::race::OnceNonZeroUsize [−] [src]

    pub struct OnceNonZeroUsize { /* fields omitted */ }

A thread-safe cell which can be written to only once.

## Implementations

### `impl OnceNonZeroUsize` [src]

#### `pub const fn new() -> OnceNonZeroUsize` [src]

Creates a new empty cell.

#### `pub fn get(&self) -> Option<NonZeroUsize>` [src]

Gets the underlying value.

#### `pub fn set(&self, value: NonZeroUsize) -> Result<(), ()>` [src]

Sets the contents of this cell to `value`.

Returns `Ok(())` if the cell was empty and `Err(())` if it was full.

#### `pub fn get_or_init<F>(&self, f: F) -> NonZeroUsize where
F: FnOnce() -> NonZeroUsize,` [src]

Gets the contents of the cell, initializing it with `f` if the cell was empty.

If several threads concurrently run `get_or_init`, more than one `f` can be called. However, all threads will return the same value, produced by some `f`.

#### `pub fn get_or_try_init<F, E>(&self, f: F) -> Result<NonZeroUsize, E> where
F: FnOnce() -> Result<NonZeroUsize, E>,` [src]

Gets the contents of the cell, initializing it with `f` if the cell was empty. If the cell was empty and `f` failed, an error is returned.

If several threads concurrently run `get_or_init`, more than one `f` can be called. However, all threads will return the same value, produced by some `f`.

## Trait Implementations

### `impl Debug for OnceNonZeroUsize` [src]

#### `fn fmt(&self, f: &mut Formatter<'_>) -> Result` [src]

Formats the value using the given formatter. Read more

### `impl Default for OnceNonZeroUsize` [src]

#### `fn default() -> OnceNonZeroUsize` [src]

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

## Auto Trait Implementations

### `impl RefUnwindSafe for OnceNonZeroUsize`

### `impl Send for OnceNonZeroUsize`

### `impl Sync for OnceNonZeroUsize`

### `impl Unpin for OnceNonZeroUsize`

### `impl UnwindSafe for OnceNonZeroUsize`

## Blanket Implementations

### `impl<T> Any for T where
T: 'static + ?Sized,` [src]

#### `pub fn type_id(&self) -> TypeId` [src]

Gets the `TypeId` of `self`. Read more

### `impl<T> Borrow<T> for T where
T: ?Sized,` [src]

#### `pub fn borrow(&self) -> &T` [src]

Immutably borrows from an owned value. Read more

### `impl<T> BorrowMut<T> for T where
T: ?Sized,` [src]

#### `pub fn borrow_mut(&mut self) -> &mut T` [src]

Mutably borrows from an owned value. Read more

### `impl<T> From<T> for T` [src]

#### `pub fn from(t: T) -> T` [src]

Performs the conversion.

### `impl<T, U> Into<U> for T where
U: From<T>,` [src]

#### `pub fn into(self) -> U` [src]

Performs the conversion.

### `impl<T, U> TryFrom<U> for T where
U: Into<T>,` [src]

#### `type Error = Infallible`

The type returned in the event of a conversion error.

#### `pub fn try_from(value: U) -> Result<T, <T as TryFrom<U>>::Error>` [src]

Performs the conversion.

### `impl<T, U> TryInto<U> for T where
U: TryFrom<T>,` [src]

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

The type returned in the event of a conversion error.

#### `pub fn try_into(self) -> Result<U, <U as TryFrom<T>>::Error>` [src]

Performs the conversion.