object::reserve

Increase the capacity to at least a certain amount.

Synopsis

void
reserve(
    std::size_t new_capacity);

This increases the capacity() to a value that is greater than or equal to new_capacity. If new_capacity > capacity(), new memory is allocated. Otherwise, the call has no effect. The number of elements and therefore the size() of the container is not changed.

If new memory is allocated, all iterators including any past-the-end iterators, and all references to the elements are invalidated. Otherwise, no iterators or references are invalidated.

Complexity

Constant or average case linear in size(), worst case quadratic.

Exception Safety

Strong guarantee. Calls to memory_resource::allocate may throw.

Parameters

Name	Description
`new_capacity`	The new minimum capacity.

Exceptions

Type	Thrown On
`std::length_error`	`new_capacity > max_size()`