CppCon 2019

This talk is about a new feature in C++20 which has significant implications
for compile-time programming: allowing class types to be used in non-type
template parameters (NTTPs).

Several talks at last year's CppCon pushed the boundaries of compile-time
string processing, with a common catch: reliance on an extension to C++'s UDLs
that the committee has been refusing to standardise since 2013. That extension
provides an easy way to get string data into the type system rather than just
into constexpr variables,

The talk will cover what that extension is, why it was never standardised, and
how class-type NTTPs make it unnecessary. We'll then talk about what can
and can't be done with class-type NTTPs, what the challenges of adding them to the
language were, and take a look at some things they've been used for.