Embedded Template LibraryUtilitiesnull_typenull_typeHeader: null_type.hSince: TBCA placeholder type to use as unique default types in a list of template type parameters.template <size_t N> class null_type { };Example template <typename T1 = etl::null_type<1>, typename T2 = etl::null_type<2>> class MyClassnth_typenullptr