Product

using libsemigroups::KoniecznyTraits::Product = ::libsemigroups::Product<element_type>

Defined in adapters.hpp.

Specialisations of this struct should be stateless trivially default constructible with a call operator of signature void operator()(TElementType& xy, TElementType const& x, TElementType const& y, size_t = 0) (possibly noexcept, inline and/or constexpr also).

The call operator should change xy in-place to be the product of x and y. The 4th parameter is optional and it can be used as an index for static thread local storage, that might be required for forming the product of x and y. The purpose of the 1st parameter is to avoid repeated allocations of memory to hold temporary products that are discarded soon after they are created.

The second template parameter exists for SFINAE in overload resolution.

Template Parameters

• TElementType: the type of the elements of a semigroup.

Used by:

• ActionTraits

• FroidurePinTraits

• CongruenceByPairs

• SchreierSimsTraits

Example

template <>
struct Product<size_t> {
  void operator()(size_t& xy, size_t x, size_t y, size_t = 0) const
  noexcept {
    xy = x * y;
  }
};