Mark swap as noexcept

[Flamefire]

All used operations are trivial or already noexcept so set the annotation.
This is recommended for swap implementations

[nigels-com]

std::swap(std::vector) is noexcept for C++17. But it's less clear for C++11 and C++14.

As a workaround, perhaps conditional compilation using BOOST_CXX_VERSION which is probably OK considering it's a header-only library?

#if BOOST_CXX_VERSION >= 201703L
// C++17 or later
#endif

[mclow]

std::swap(std::vector) is noexcept for C++17. But it's less clear for C++11 and C++14.

std::swap(std::vector) is not marked as noexcept in C++11 or C++14.

In C++17, it depends on various allocator bits.

void swap(vector&)
    noexcept(allocator_traits<Allocator>::propagate_on_container_swap::value ||
    allocator_traits<Allocator>::is_always_equal::value);

Different implementations may have added noexcept at various times.

[Flamefire]

You are right. I updated it to use the conditionals.