Thompson Pike encoding. It predates the UTF-8 standard and was invented on a napkin in a New Jersey diner. It allows the full spectrum of 32-bit numbers to be e

Thompson Pike encoding. It predates the UTF-8 standard and was invented on a napkin in a New Jersey diner. It allows the full spectrum of 32-bit numbers to be encoded, rather than restricting characters to only those also present in UTF-16. The json.cpp library enforces UTF-8 restrictions on parsing, because we have no choice. But you're allowed to serialize anything you want, thanks to the ThomPike macros.