80f9458cf3
Implements P2495R3 <https://wg21.link/P2495R3> - https://eel.is/c++draft/version.syn#headerref:%3csstream%3e - https://eel.is/c++draft/stringbuf - https://eel.is/c++draft/stringbuf.general - https://eel.is/c++draft/stringbuf.cons - https://eel.is/c++draft/stringbuf.members - https://eel.is/c++draft/istringstream - https://eel.is/c++draft/istringstream.general - https://eel.is/c++draft/istringstream.cons - https://eel.is/c++draft/istringstream.members - https://eel.is/c++draft/ostringstream - https://eel.is/c++draft/ostringstream.general - https://eel.is/c++draft/ostringstream.cons - https://eel.is/c++draft/ostringstream.members - https://eel.is/c++draft/stringstream - https://eel.is/c++draft/stringstream.general - https://eel.is/c++draft/stringstream.cons - https://eel.is/c++draft/stringstream.members References: - https://eel.is/c++draft/string.streams