LazyArray

Struct LazyArray 

Source
pub struct LazyArray<T> { /* private fields */ }
Expand description

A collection with a size defined at creation, but where entries are initialized later.

It is useful when you are reading nodes of an acyclic graph, where entries can be read as you need them.

§Example

#[derive(Debug, Eq, PartialEq)]
struct Entry<'heap> {
    value: i32,
    next: Option<&'heap Entry<'heap>>,
}

fn do_something<'heap>(heap: &'heap LazyArray<Entry<'heap>>) {
    let entry_0 = heap.get_or_insert(3, Entry { value: 123, next: None });
    let entry_1 = heap.get_or_insert(6, Entry { value: 456, next: Some(entry_0) });
    assert_eq!(Some(123), entry_1.next.map(|inner| inner.value));
    assert_eq!(None, heap.get(2));
}

Implementations§

Source§

impl<T> LazyArray<T>

Source

pub fn new(capacity: usize) -> Self

Source

pub fn get_or_insert(&self, index: usize, t: T) -> &T

Source

pub fn get(&self, index: usize) -> Option<&T>

Trait Implementations§

Source§

impl<T: Debug> Debug for LazyArray<T>

Source§

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

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

impl<T> Default for LazyArray<T>

Source§

fn default() -> Self

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

impl<T> Drop for LazyArray<T>

Source§

fn drop(&mut self)

Executes the destructor for this type. Read more

Auto Trait Implementations§

§

impl<T> Freeze for LazyArray<T>

§

impl<T> RefUnwindSafe for LazyArray<T>
where T: RefUnwindSafe,

§

impl<T> !Send for LazyArray<T>

§

impl<T> !Sync for LazyArray<T>

§

impl<T> Unpin for LazyArray<T>

§

impl<T> UnwindSafe for LazyArray<T>
where T: RefUnwindSafe,

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<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, 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.