Boost C++ Libraries: Ticket #7652: compile-time checked access

Marshall Clow — Tue, 18 Dec 2012 16:24:46 GMT

Yes, it would - but would people actually use it?

Do people use:

std::array<int, 2> arr;
std::get<2>(arr) = -1;

in C++11 - or do they just write arr[2] = -1; ?

boost::array (and std::array, and std::vector) all have runtime checking through the member function at.

boost::array<int, 2> arr;
arr.at(2) = -1;    // will throw an exception

Marshall Clow — Tue, 18 Dec 2012 18:01:02 GMT

In [82083], I added support for std::get<> to Boost.Array, so you can write

boost::array<int, 2> arr;
std::get<2>(arr) = -1;

and get a compile-time error.

Right now, it's only turned on for C++11, but I might be able to make it work for C++03 systems.

anonymous — Wed, 19 Dec 2012 06:26:25 GMT

The stl-version of VS 2008 has the same code for "get" and std::tr1::array<T,N> and it compiles fine with C++03, so it works at least for that compiler.

Tobias Loew — Wed, 19 Dec 2012 07:39:58 GMT

I made the last comment but forgot to login, sorry

Marshall Clow — Thu, 27 Dec 2012 21:57:06 GMT

I also added overloads of boost::get for use on C++03

status, milestone changed

Marshall Clow — Thu, 03 Jan 2013 17:27:41 GMT

status new → assigned
milestone To Be Determined → Boost 1.54.0

Marshall Clow — Tue, 12 Feb 2013 18:11:23 GMT

Also, in [82834], I marked a bunch of methods of Boost.Array as "constexpr".