All Smart-Pointer Operations

All Smart-Pointer Operations

A compact scan page for creation, ownership queries, casts, resets, and observer operations on standard smart pointers.

How to use this reference page

Use reference pages to confirm names, categories, nearby facilities, and the constraints that matter before writing or reviewing code.

Scan the top of the page first to identify the primary types, functions, or algorithm families involved.
Use the nearby-page links when your question is really about a companion header, related algorithm family, or broader subsystem.
Validate tricky behavior with a small compileable example before relying on memory for details like invalidation, ordering, allocation, or lifetime rules.

All Smart-Pointer Operations

Unique ownership operations

std::make_unique
std::make_unique_for_overwrite
release
reset
get
swap

Shared ownership operations

std::make_shared
std::make_shared_for_overwrite
std::allocate_shared
std::allocate_shared_for_overwrite
use_count
unique
reset
swap
aliasing constructor patterns

Weak ownership operations

lock
expired
use_count
reset
owner_before

Shared-pointer casts

std::static_pointer_cast
std::dynamic_pointer_cast
std::const_pointer_cast
std::reinterpret_pointer_cast

Practical rules

Prefer make_unique and make_shared over naked new at call sites.
Treat use_count() as observational, not as a synchronization primitive.
Use weak_ptr::lock() to safely obtain temporary shared ownership.

Example in practice

#include <memory>

int main() {
    auto owner = std::make_unique<int>(42);
    auto shared = std::make_shared<int>(*owner);
    owner.reset();
    return *shared;
}