To indicate success of a conversion, the public API has previously only
supported registering member functions of the form To (From::*)(bool *).
When adding custom converters for types that cannot be modified, this is
usually not a possibility.
As an alternative, this patch adds support for std::optional in the
UnaryFunction overload of QMetaType::registerConverter. If the returned
optional has no value, the conversion is considered failed.
Task-number: QTBUG-92902
Change-Id: Ibac52d2cb9b5a2457081b4bebb0def1f03e3c55d
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>
Reviewed-by: Fabian Kosmale <fabian.kosmale@qt.io>
7a7051b58f