Struct OnceCellBrand 

pub struct OnceCellBrand;

Brand for std::cell::OnceCell.

Trait Implementations

impl Clone for OnceCellBrand

fn clone(&self) -> OnceCellBrand

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for OnceCellBrand

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

Formats the value using the given formatter.

impl Default for OnceCellBrand

fn default() -> OnceCellBrand

Returns the “default value” for a type.

impl Hash for OnceCellBrand

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 OnceCellBrand

Generated implementation of Kind_ad6c20556a82a1f0 for OnceCellBrand.

type Of<A> = OnceCell<A>

impl Once for OnceCellBrand

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

Creates a new, uninitialized Once container.

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

Type Signature

forall a. Once OnceCellBrand => () -> OnceCell a

Type Parameters

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

Returns

A new, empty OnceCell.

Examples

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

let cell = <OnceCellBrand as Once>::new::<i32>();
assert_eq!(<OnceCellBrand 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 OnceCell if it has been initialized, otherwise it returns None.

Type Signature

forall a. Once OnceCellBrand => OnceCell a -> Option a

Type Parameters

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

Parameters

• a: The OnceCell.

Returns

A reference to the value, or None if uninitialized.

Examples

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

let cell = <OnceCellBrand as Once>::new::<i32>();
assert_eq!(<OnceCellBrand as Once>::get(&cell), None);
<OnceCellBrand as Once>::set(&cell, 42).unwrap();
assert_eq!(<OnceCellBrand 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 OnceCell if it has been initialized, otherwise it returns None.

Type Signature

forall a. Once OnceCellBrand => OnceCell a -> Option a

Type Parameters

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

Parameters

• a: The OnceCell.

Returns

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

Examples

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

let mut cell = <OnceCellBrand as Once>::new::<i32>();
<OnceCellBrand as Once>::set(&cell, 42).unwrap();
if let Some(val) = <OnceCellBrand as Once>::get_mut(&mut cell) {
    *val += 1;
}
assert_eq!(<OnceCellBrand 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 OnceCell. If the OnceCell is already initialized, it returns the value in the Err variant.

Type Signature

forall a. Once OnceCellBrand => (OnceCell a, a) -> Result<(), a>

Type Parameters

• A: The type of the value to set.

Parameters

• a: The OnceCell.
• 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::OnceCellBrand;

let cell = <OnceCellBrand as Once>::new::<i32>();
assert!(<OnceCellBrand as Once>::set(&cell, 42).is_ok());
assert!(<OnceCellBrand 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 OnceCell. If the OnceCell is not initialized, it initializes it using the provided closure f and then returns a reference to the value.

Type Signature

forall a. Once OnceCellBrand => (OnceCell 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 OnceCell.
• f: The initialization function.

Returns

A reference to the value.

Examples

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

let cell = <OnceCellBrand as Once>::new::<i32>();
assert_eq!(*<OnceCellBrand as Once>::get_or_init(&cell, || 42), 42);
assert_eq!(*<OnceCellBrand 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 OnceCell and returns the value stored in it if it has been initialized, otherwise it returns None.

Type Signature

forall a. Once OnceCellBrand => OnceCell a -> Option a

Type Parameters

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

Parameters

• a: The OnceCell.

Returns

The value, or None if uninitialized.

Examples

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

let cell = <OnceCellBrand as Once>::new::<i32>();
<OnceCellBrand as Once>::set(&cell, 42).unwrap();
assert_eq!(<OnceCellBrand 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 OnceCell, leaving the OnceCell in an uninitialized state. It returns the value if it was initialized, otherwise it returns None.

Type Signature

forall a. Once OnceCellBrand => OnceCell a -> Option a

Type Parameters

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

Parameters

• a: The OnceCell.

Returns

The value, or None if uninitialized.

Examples

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

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

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

impl Ord for OnceCellBrand

fn cmp(&self, other: &OnceCellBrand) -> 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 OnceCellBrand

fn eq(&self, other: &OnceCellBrand) -> 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 OnceCellBrand

fn partial_cmp(&self, other: &OnceCellBrand) -> 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 OnceCellBrand

impl Eq for OnceCellBrand

impl StructuralPartialEq for OnceCellBrand