allocator_api2

Module vec

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Expand description

A contiguous growable array type with heap-allocated contents, written Vec<T>.

Vectors have O(1) indexing, amortized O(1) push (to the end) and O(1) pop (from the end).

Vectors ensure they never allocate more than isize::MAX bytes.

§Examples

You can explicitly create a Vec with Vec::new:

let v: Vec<i32> = Vec::new();

…or by using the vec! macro:

let v: Vec<i32> = vec![];

let v = vec![1, 2, 3, 4, 5];

let v = vec![0; 10]; // ten zeroes

You can push values onto the end of a vector (which will grow the vector as needed):

let mut v = vec![1, 2];

v.push(3);

Popping values works in much the same way:

let mut v = vec![1, 2];

let two = v.pop();

Vectors also support indexing (through the Index and IndexMut traits):

let mut v = vec![1, 2, 3];
let three = v[2];
v[1] = v[1] + 5;

Structs§

  • A draining iterator for Vec<T>.
  • An iterator that moves out of a vector.
  • A splicing iterator for Vec.
  • A contiguous growable array type, written as Vec<T>, short for ‘vector’.