The formatter prototype is
// A formatter for objects of type T.
template <typename T, typename Char = char, typename Enable = void>
struct formatter {
explicit formatter(internal::dummy_formatter_arg);
};
so we should use this order in the example as well.
In addition we use Char instead of plain char to not confuse the reader
as this name is totally arbitrary.
* Clarify usage of fmt::arg
Document that fmt::arg takes a non-owning
reference, even if that reference is to
a temporary. As such, users should make sure
the lifetime of the reference lasts as long
as the named argument.
* Clean up language
Remove mentions of `std::reference_wrapper` and rvalues
in favor of more common terminology like dangling references.
Since C++17, using template specialization 'std::allocator<void>' in any shape or form (even just mentioning it) is deprecated! A simple workaround is replacing 'void' by another (preferably empty) type, e.g. 'fmt::monostate'.
Found by Clang 9 in Visual Studio.
C++17 deprecated 'std::result_of' in favour of 'std::invoke_result' and will ban it outright in C++20. Therefore
- implement 'internal::result_of' in terms of 'std::invoke_result' when compiling C++17 mode.
- implement 'internal::result_of' in terms of 'std::result_of' when compiling in modes C++11 or C++14.
Signed-off-by: Daniela Engert <dani@ngrt.de>
Howard Hinnant's 'date' library recently gained these two new formatting specifiers. This implementation in {fmt} includes support for 'std::chrono::duration' specializations with floating-point representation types and user-definable precision.
Signed-off-by: Daniela Engert <dani@ngrt.de>
Mostly equivalent to 'sprintf(const S &format, const Args & ... args)' but generates at most 'n' characters through output iterator 'it'. The output type is the same as with 'format_to_n'.
Signed-off-by: Daniela Engert <dani@ngrt.de>
