yorel::yomm2::aggregate
defined in <yorel/yomm2/core.hpp>, also provided by <yorel/yomm2/keywords.hpp>
template<typename... T> struct aggregate;
An instance of aggregate<T...> contains one T sub-object for each
specified T, just like a std::tuple.
aggregate provides a convenient way to instantiate a collection of YOMM2
registration objects. Typically, the name of the variable
does not matter, and YOMM2_GENSYM can be used to generated that single-use
identifier.
Unlike typical std::tuple<typename... T> implementations, aggregate can
handle large numbers of Ts. For example, clang++-12 has a limit of 1024
types, which can be reached easily when writing templatized method
definitions.
#include <yorel/yomm2/keywords.hpp>
#include <yorel/yomm2/templates.hpp>
using namespace yorel::yomm2;
struct Animal { virtual ~Animal() {} };
struct Dog : Animal {};
struct Cat : Animal {};
aggregate<
class_declaration<types<Animal>>,
class_declaration<types<Dog, Animal>>,
class_declaration<types<Cat, Animal>>
> YOMM2_GENSYM;