Perfect forwarding is a technique in C++ used to preserve the reference type of a value when passed to a function through another function. For example,
foo(
T |
T& |
T&& |
|
|---|---|---|---|
T = U |
U |
U& |
U&& |
T = U& |
U& |
U& |
U& |
T = U&& |
U&& |
U& |
U&& |