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| author | Jonathan Wakely <jwakely@redhat.com> | 2019-04-03 10:47:47 +0100 |
|---|---|---|
| committer | Jonathan Wakely <redi@gcc.gnu.org> | 2019-04-03 10:47:47 +0100 |
| commit | 0cb78ef4bcd216413199f9f27eed0ea0a56dd8da (patch) | |
| tree | c4d7fd4a00fd3526c53a1055a9e91973a4a0fd1e /libstdc++-v3/include/std/string | |
| parent | 3a3976b14e329421e51a2aa43e516a6871cb5e6b (diff) | |
| download | gcc-0cb78ef4bcd216413199f9f27eed0ea0a56dd8da.zip gcc-0cb78ef4bcd216413199f9f27eed0ea0a56dd8da.tar.gz gcc-0cb78ef4bcd216413199f9f27eed0ea0a56dd8da.tar.bz2 | |
Define std::hash specializations for C++17 PMR strings
These hash specializations should have been added when the pmr::string
and related typedefs were added.
* include/std/string (__hash_string_base): New class template defining
operator() for hashing strings.
(hash<pmr::string>, hash<pmr::u8string>, hash<pmr::u16string>)
(hash<pmr::u32string>, hash<pmr::wstring>): Define for C++17.
* testsuite/21_strings/basic_string/hash/hash.cc: New test.
* testsuite/21_strings/basic_string/hash/hash_char8_t.cc: New test.
From-SVN: r270116
Diffstat (limited to 'libstdc++-v3/include/std/string')
| -rw-r--r-- | libstdc++-v3/include/std/string | 35 |
1 files changed, 35 insertions, 0 deletions
diff --git a/libstdc++-v3/include/std/string b/libstdc++-v3/include/std/string index 100c6c84..6ccc06f 100644 --- a/libstdc++-v3/include/std/string +++ b/libstdc++-v3/include/std/string @@ -74,6 +74,41 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION using wstring = basic_string<wchar_t>; #endif } // namespace pmr + + template<typename _Str> + struct __hash_string_base + : public __hash_base<size_t, _Str> + { + size_t + operator()(const _Str& __s) const noexcept + { return hash<basic_string_view<typename _Str::value_type>>{}(__s); } + }; + + template<> + struct hash<pmr::string> + : public __hash_string_base<pmr::string> + { }; +#ifdef _GLIBCXX_USE_CHAR8_T + template<> + struct hash<pmr::u8string> + : public __hash_string_base<pmr::u8string> + { }; +#endif + template<> + struct hash<pmr::u16string> + : public __hash_string_base<pmr::u16string> + { }; + template<> + struct hash<pmr::u32string> + : public __hash_string_base<pmr::u32string> + { }; +#ifdef _GLIBCXX_USE_WCHAR_T + template<> + struct hash<pmr::wstring> + : public __hash_string_base<pmr::wstring> + { }; +#endif + _GLIBCXX_END_NAMESPACE_VERSION } // namespace std #endif // C++17 |