Rodin›Utility

BottomTemplate

Metafunction to extract the innermost (bottom) type from nested templates.

Defined in Rodin/Utility/BottomTemplate.h

template <
  class T>
struct BottomTemplate;

Specializations

SpecializationDescription
T<S>
Full specialization
template <
  template< class > class T,
  class S>
struct BottomTemplate<
  T< S >>;
Specialization for single-parameter template instantiations.
Template parameters
T The type to extract the bottom type from.

BottomTemplate recursively unwraps template wrappers to find the innermost type. For a non-template type T, the result is T itself. For a nested template like A<B<C<D>>>, the result is D.

Example usage:

using Nested = std::vector<std::optional<int>>;
using Bottom = BottomTemplate<Nested>::Type;
// Bottom is int (assuming single-param template specialization)

Public types

using Type = T
The type itself when T is not a template instantiation.