Simplify string_view detection

This commit is contained in:
Victor Zverovich 2018-09-22 19:46:57 -07:00
parent 2def9e4c82
commit d41be23acd

View File

@ -170,11 +170,10 @@
(__cplusplus > 201402L || defined(_LIBCPP_VERSION))) || \
(defined(_MSVC_LANG) && _MSVC_LANG > 201402L && _MSC_VER >= 1910)
# include <string_view>
# define FMT_USE_STD_STRING_VIEW
#elif (FMT_HAS_INCLUDE(<experimental/string_view>) && \
__cplusplus >= 201402L)
# define FMT_STRING_VIEW std::basic_string_view
#elif FMT_HAS_INCLUDE(<experimental/string_view>) && __cplusplus >= 201402L
# include <experimental/string_view>
# define FMT_USE_EXPERIMENTAL_STRING_VIEW
# define FMT_STRING_VIEW std::experimental::basic_string_view
#endif
// std::result_of is defined in <functional> in gcc 4.4.
@ -238,18 +237,6 @@ class basic_string_view {
typedef Char char_type;
typedef const Char *iterator;
// Standard basic_string_view type.
#if defined(FMT_USE_STD_STRING_VIEW)
typedef std::basic_string_view<Char> type;
#elif defined(FMT_USE_EXPERIMENTAL_STRING_VIEW)
typedef std::experimental::basic_string_view<Char> type;
#else
struct type {
const char *data() const { return FMT_NULL; }
size_t size() const { return 0; }
};
#endif
FMT_CONSTEXPR basic_string_view() FMT_NOEXCEPT : data_(FMT_NULL), size_(0) {}
/** Constructs a string reference object from a C string and a size. */
@ -271,8 +258,10 @@ class basic_string_view {
const std::basic_string<Char, Alloc> &s) FMT_NOEXCEPT
: data_(s.data()), size_(s.size()) {}
FMT_CONSTEXPR basic_string_view(type s) FMT_NOEXCEPT
#ifdef FMT_STRING_VIEW
FMT_CONSTEXPR basic_string_view(FMT_STRING_VIEW<Char> s) FMT_NOEXCEPT
: data_(s.data()), size_(s.size()) {}
#endif
/** Returns a pointer to the string data. */
FMT_CONSTEXPR const Char *data() const { return data_; }