neargye-wg21 / charconv-constexpr-proposal

WG21 Proposal: Add Constexpr Modifiers to Functions to_chars and from_chars

Add Constexpr Modifiers to Functions to_chars and from_chars for Integral Types

References

• https://github.com/microsoft/STL/blob/master/stl/inc/charconv

Tested

Tested on MS/STL charconv set tests and small constexpr set tests.

• GCC 10
• Clang 10
• Visual Studio 2019