96d67da420
In C++20 std::basic_string_view has gained a range constructor (like QStringView always had), but that range constructor has been made explicit. This means we can't just pass a QString(View) to a function taking a u16string_view. The consensus seems to be that that types that should implictly convert towards stdlib's string views should do that via implicit conversion operators. This patch adds them for * QByteArrayView => std::string_view * QString(View) => std::u16string_view * QUtf8StringView => std::string_view or std::u8string_view, depending on the storage_type QLatin1StringView doesn't have a matching std:: view so I'm not enabling its conversion. QByteArray poses a challenge, in that it already defines a conversion towards const char *. (One can disable that conversion with a macro.) That conversion makes it impossible to support: QByteArray ba; std::string_view sv1(ba); // 1 std::string_view sv2 = ba; // 2 because: * if only operator const char *() is defined, then (2) doesn't work (situation right now); * if both conversions to const char * and string_view are defined, then (1) is ambiguous on certain compilers (MSVC, QCC). Interestingly enough, not on GCC/Clang, but only in C++17 and later modes. I can't kill the conversion towards const char * (API break, and we use it *everywhere* in Qt), hence, QByteArray does not get the implicit conversion, at least not in this patch. [ChangeLog][QtCore][QByteArrayView] Added an implicit conversion operator towards std::string_view. [ChangeLog][QtCore][QString] Added an implicit conversion operator towards std::u16string_view. [ChangeLog][QtCore][QStringView] Added an implicit conversion operator towards std::u16string_view. [ChangeLog][QtCore][QUtf8StringView] Added an implicit conversion operator towards std::string_view (QUtf8StringView is using char as its storage type in Qt 6). Note that QUtf8StringView is planned to use char8_t in Qt 7, therefore it is expected that the conversion will change towards std::u8string_view in Qt 7. Change-Id: I6d3b64d211a386241ae157765cd1b03f531f909a Reviewed-by: Thiago Macieira <thiago.macieira@intel.com> |
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| .. | ||
| CMakeLists.txt | ||
| tst_qbytearrayview.cpp | ||