Le 10/12/12 22:16, Jeffrey Yasskin a écrit :
On Wed, Nov 28, 2012 at 2:48 AM, Rob Stewart <robertstewart@comcast.net> wrote:
o char const (&)[N] This constructor is dangerous in cases like
char space[100]; snprintf(space, 100, "format", args); string_ref str(space);
so I think most of the suggestions on this list have moved toward a more explicit but very verbose string_ref::from_literal("foo\0bar"). I guess this is because the proposed Boost interface should work on C++98 compilers. This doesn't mean that it could not provide something more adapted to C++11.
http://www.open-std.org/JTC1/SC22/WG21/docs/papers/2012/n3468.pdf proposed adding various user-defined literals to the standard library. What do you folks think of string_ref UDLs like:
namespace boost { namespace string_literals { #define BOOST_DEFINE_STRING_REF_LITERAL(CharT) \ constexpr basic_string_ref<CharT> operator"" _s( \ const CharT* str, size_t len) { \ return basic_string_ref<CharT>(str, len); \ } BOOST_DEFINE_STRING_REF_LITERAL(char); BOOST_DEFINE_STRING_REF_LITERAL(wchar_t); BOOST_DEFINE_STRING_REF_LITERAL(char16_t); BOOST_DEFINE_STRING_REF_LITERAL(char32_t); #undef BOOST_DEFINE_STRING_REF_LITERAL } }
using namespace boost::string_literals; constexpr boost::string_ref glbl = "Constexpr"_s; constexpr boost::string_ref contains_null = "Const\0expr"_s; static_assert(contains_null.at(6) == 'e', "Expect string to extend past null"); static_assert(glbl.size() == sizeof("Constexpr") - 1, "Expect string to omit trailing null");
(Tested with Clang r163674)
?
I think that the suffix _s is used also for seconds. Can both be used without ambiguity? If not, is _str too long for a suffix for strings? Vicente