P0539R5.pdf

P0539R5 proposes adding a `wideint` template class to the C++ standard library for handling large integers, providing a generic solution for big numbers, and addressing the need for a cross-platform solution. The proposal revises the previous version, P0539R4, and includes changes such as syncing with P1889R1, using LaTeX for wording and paper, and using the spaceship operator. The `wideinteger` class is designed to mimic the behavior of built-in integral types, with features like not allocating memory, being a standard layout type, and being trivially copyable and destructible. The proposal also discusses design limitations, interoperability with other types, and potential future extensions. A proof of concept implementation is available, and the proposal includes recommended feature-testing macro names and proposed wording for the C++ standard library.