string_view was implicitly convertible to std::string, but
std::string_view is only explicitly convertible. This makes the
`operator std::string` explicit to be more compatible, and re-adds a
bunch of explicit string casts to the code where needed.
(This also fixes the build if changing the standard to c++17)
It doesn't currently work for either test suite: we get a
`MemorySanitizer: use-of-uninitialized-value` immediately from both test
suites, with what looks like catch2 or gtest internals.
So just disable it for now.
They are fairly useless under stdlibc++ because it doesn't have the
required annotations on stl mutexes and locks, so we just get tons of
useless warnings.
Pre-C++17 char_traits::compare isn't constexpr so we can't constexpr the
find/rfind methods that use it.
begin() etc, however, can be constexpr (and need to be for some of the
other constexpr methods here that use them).
Howard Hinnart's date.h is the library that was accepted as C++20
date/calendar support, so this is essentially a backport of C++20 date
time support.
(It does support timezone support, but requires more of the library and
that seems like overkill for what we need; this just prints UTC
timestamps instead, which need only a header-only include).
This was being used to get at gcc/clang's __builtin_expect, but we don't
really need that: we can just avoid the check entirely when not in debug
mode which should be even faster.
fromEnv here wasn't usefully templatized (the base template basically
couldn't be used for anything except a string anyway), so just replaced
it with the overloads we need and moved the implementations out of the
header.
Renames the cmake Catch2 test target to "catch" (instead of "check") and
adds a "rungtest" for gtest (because the "gtest" target is already taken
by the gtest library itself), and then repurposes the "check" target to
run both test suite binaries.
Also updates the top-level Makefile to do the same thing, except that
there the gtest target is just "gtest" instead of "rungtest".
