Struct OnceLockBrand 

pub struct OnceLockBrand;

Brand for std::sync::OnceLock.

Trait Implementations

impl Clone for OnceLockBrand

fn clone(&self) -> OnceLockBrand

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for OnceLockBrand

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

Formats the value using the given formatter.

impl Default for OnceLockBrand

fn default() -> OnceLockBrand

Returns the “default value” for a type.

impl Hash for OnceLockBrand

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

Feeds this value into the given Hasher.

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

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl Kind_ad6c20556a82a1f0 for OnceLockBrand

Generated implementation of Kind_ad6c20556a82a1f0 for OnceLockBrand.

type Of<A> = OnceLock<A>

impl Once for OnceLockBrand

fn new<A>() -> <Self as Once>::Of<A>

Creates a new, uninitialized Once container.

This method creates a new instance of the OnceLock that is initially empty.

Type Signature

forall a. Once OnceLockBrand => () -> OnceLock a

Type Parameters

• A: The type of the value to be stored in the container.

Returns

A new, empty OnceLock.

Examples

use fp_library::classes::once::Once;
use fp_library::brands::OnceLockBrand;

let cell = <OnceLockBrand as Once>::new::<i32>();
assert_eq!(<OnceLockBrand as Once>::get(&cell), None);

fn get<A>(a: &<Self as Once>::Of<A>) -> Option<&A>

Gets a reference to the value if it has been initialized.

This method returns a reference to the value stored in the OnceLock if it has been initialized, otherwise it returns None.

Type Signature

forall a. Once OnceLockBrand => OnceLock a -> Option a

Type Parameters

• A: The type of the value stored in the container.

Parameters

• a: The OnceLock.

Returns

A reference to the value, or None if uninitialized.

Examples

use fp_library::classes::once::Once;
use fp_library::brands::OnceLockBrand;

let cell = <OnceLockBrand as Once>::new::<i32>();
assert_eq!(<OnceLockBrand as Once>::get(&cell), None);
<OnceLockBrand as Once>::set(&cell, 42).unwrap();
assert_eq!(<OnceLockBrand as Once>::get(&cell), Some(&42));

fn get_mut<A>(a: &mut <Self as Once>::Of<A>) -> Option<&mut A>

Gets a mutable reference to the value if it has been initialized.

This method returns a mutable reference to the value stored in the OnceLock if it has been initialized, otherwise it returns None.

Type Signature

forall a. Once OnceLockBrand => OnceLock a -> Option a

Type Parameters

• A: The type of the value stored in the container.

Parameters

• a: The OnceLock.

Returns

A mutable reference to the value, or None if uninitialized.

Examples

use fp_library::classes::once::Once;
use fp_library::brands::OnceLockBrand;

let mut cell = <OnceLockBrand as Once>::new::<i32>();
<OnceLockBrand as Once>::set(&cell, 42).unwrap();
if let Some(val) = <OnceLockBrand as Once>::get_mut(&mut cell) {
    *val += 1;
}
assert_eq!(<OnceLockBrand as Once>::get_mut(&mut cell), Some(&mut 43));

fn set<A>(a: &<Self as Once>::Of<A>, value: A) -> Result<(), A>

Sets the value of the container.

This method attempts to set the value of the OnceLock. If the OnceLock is already initialized, it returns the value in the Err variant.

Type Signature

forall a. Once OnceLockBrand => (OnceLock a, a) -> Result<(), a>

Type Parameters

• A: The type of the value to set.

Parameters

• a: The OnceLock.
• value: The value to set.

Returns

Ok(()) on success, or Err(value) if already initialized.

Examples

use fp_library::classes::once::Once;
use fp_library::brands::OnceLockBrand;

let cell = <OnceLockBrand as Once>::new::<i32>();
assert!(<OnceLockBrand as Once>::set(&cell, 42).is_ok());
assert!(<OnceLockBrand as Once>::set(&cell, 10).is_err());

fn get_or_init<A, B: FnOnce() -> A>(a: &<Self as Once>::Of<A>, f: B) -> &A

Gets the value, initializing it with the closure f if it is not already initialized.

This method returns a reference to the value stored in the OnceLock. If the OnceLock is not initialized, it initializes it using the provided closure f and then returns a reference to the value.

Type Signature

forall a. Once OnceLockBrand => (OnceLock a, () -> a) -> a

Type Parameters

• A: The type of the value stored in the container.
• B: The type of the initialization function.

Parameters

• a: The OnceLock.
• f: The initialization function.

Returns

A reference to the value.

Examples

use fp_library::classes::once::Once;
use fp_library::brands::OnceLockBrand;

let cell = <OnceLockBrand as Once>::new::<i32>();
assert_eq!(*<OnceLockBrand as Once>::get_or_init(&cell, || 42), 42);
assert_eq!(*<OnceLockBrand as Once>::get_or_init(&cell, || 10), 42);

fn into_inner<A>(a: <Self as Once>::Of<A>) -> Option<A>

Consumes the container and returns the value if it has been initialized.

This method consumes the OnceLock and returns the value stored in it if it has been initialized, otherwise it returns None.

Type Signature

forall a. Once OnceLockBrand => OnceLock a -> Option a

Type Parameters

• A: The type of the value stored in the container.

Parameters

• a: The OnceLock.

Returns

The value, or None if uninitialized.

Examples

use fp_library::classes::once::Once;
use fp_library::brands::OnceLockBrand;

let cell = <OnceLockBrand as Once>::new::<i32>();
<OnceLockBrand as Once>::set(&cell, 42).unwrap();
assert_eq!(<OnceLockBrand as Once>::into_inner(cell), Some(42));

fn take<A>(a: &mut <Self as Once>::Of<A>) -> Option<A>

Takes the value out of the container, leaving it uninitialized.

This method takes the value out of the OnceLock, leaving the OnceLock in an uninitialized state. It returns the value if it was initialized, otherwise it returns None.

Type Signature

forall a. Once OnceLockBrand => OnceLock a -> Option a

Type Parameters

• A: The type of the value stored in the container.

Parameters

• a: The OnceLock.

Returns

The value, or None if uninitialized.

Examples

use fp_library::classes::once::Once;
use fp_library::brands::OnceLockBrand;

let mut cell = <OnceLockBrand as Once>::new::<i32>();
<OnceLockBrand as Once>::set(&cell, 42).unwrap();
assert_eq!(<OnceLockBrand as Once>::take(&mut cell), Some(42));
assert_eq!(<OnceLockBrand as Once>::take(&mut cell), None);

type Of<A> = <OnceLockBrand as Kind_ad6c20556a82a1f0>::Of<A>

impl Ord for OnceLockBrand

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

This method returns an Ordering between self and other.

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

where Self: Sized,

Compares and returns the maximum of two values.

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

where Self: Sized,

Compares and returns the minimum of two values.

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

where Self: Sized,

Restrict a value to a certain interval.

impl PartialEq for OnceLockBrand

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

Tests for self and other values to be equal, and is used by ==.

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

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

impl PartialOrd for OnceLockBrand

fn partial_cmp(&self, other: &OnceLockBrand) -> Option<Ordering>

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

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

Tests less than (for self and other) and is used by the < operator.

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

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

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

Tests greater than (for self and other) and is used by the > operator.

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

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

impl Copy for OnceLockBrand

impl Eq for OnceLockBrand

impl StructuralPartialEq for OnceLockBrand