Struct ResizingVec

pub struct ResizingVec<T> { /* private fields */ }

Implementations

impl<T> ResizingVec<T>

pub fn new() -> Self

pub fn prefill(capacity: usize) -> Self

Pre allocates enough space so that elements with ids < reserved_space() fit without having to resize

pub fn reserved_space(&self) -> usize

Returns the amount of space length the inner vector has. Creating a fresh ResizingVec and then inserting elements at index 0 & 2 would result in reserved_space() returning 3 as at position 1 would be an empty value

pub fn filled(&self) -> usize

Returns the amount of active values. filled() <= reserved_space() will always hold true.

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

Returns the element at the given index

pub fn get_mut(&mut self, idx: usize) -> Option<&mut T>

Returns a mutable reference to element at the given index

pub fn iter(&self) -> impl Iterator<Item = (usize, &T)> + '_

pub fn remove(&mut self, idx: usize) -> Option<T>

Removes the element at the given index and returns the remove element. If the given index is out of bounds than None is being returned

pub fn insert(&mut self, idx: usize, t: T) -> Option<T>

Inserts the element at the given index. IMPORTANT: The time complexity of this operation depends on whether it has to resize or not.

if reserved_space() < idx then insert will first insert (idx - reserved_space()) elements before inserting the given element at the index.

pub fn clear(&mut self)

Clears the vector, removing all values

pub fn resize(&mut self) -> Vec<Position>

Resizes the vector shrinks it so that every reserved space is being occupied by an element.

Examples

use resizing_vec::{ResizingVec, Position};

let mut r_vec = ResizingVec::new();
r_vec.insert(5, "6th elem".to_string());
// ResizingVec { vec: [None, None, None, None, None, Some("5th elem")], active: 1 }
assert_eq!(6, r_vec.reserved_space());
assert_eq!(1, r_vec.filled());

let new_positions = r_vec.resize();
// ResizingVec { vec: [Some("5th elem")], active: 1 }
assert_eq!(new_positions, [Position {prev_idx: 5, new_idx: 0}]);
assert_eq!(1, r_vec.reserved_space());
assert_eq!(1, r_vec.filled());

Trait Implementations

impl<T: Clone> Clone for ResizingVec<T>

fn clone(&self) -> ResizingVec<T>

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl<T: Debug> Debug for ResizingVec<T>

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

Formats the value using the given formatter.

impl<T> Default for ResizingVec<T>

fn default() -> Self

Returns the “default value” for a type.

impl<T> From<Vec<T>> for ResizingVec<T>

fn from(value: Vec<T>) -> Self

Converts to this type from the input type.

impl<T> Index<usize> for ResizingVec<T>

type Output = Option<T>

The returned type after indexing.

fn index(&self, index: usize) -> &Self::Output

Performs the indexing (container[index]) operation.

impl<T> IndexMut<usize> for ResizingVec<T>

fn index_mut(&mut self, index: usize) -> &mut Self::Output

Performs the mutable indexing (container[index]) operation.