PHP マニュアル: Allocates enough memory for a required capacity

public void Ds\Vector::allocate(int $capacity)

Ensures that enough memory is allocated for a required capacity. This removes the need to reallocate the internal as values are added.

capacity: The number of values for which capacity should be allocated.

注意:
Capacity will stay the same if this value is less than or equal to the current capacity.

値を返しません。

例1 Ds\Vector::allocate example

<?php
$vector = new \Ds\Vector();
var_dump($vector->capacity());

$vector->allocate(100);
var_dump($vector->capacity());
?>

上の例の出力は、たとえば以下のようになります。

int(10)
int(100)