Formal verification that a type has been registered in the Atlas. More...

Concept definition

template<typename T>
concept dedekind::category::IsSpecies = 
    std::regular<T> && requires { typename SpeciesTraits<T>::Domain; }

Detailed Description

Formal verification that a type has been registered in the Atlas.

The rule of thumb for value constraints across the library: std::semiregular by default (the Jlt paper's Rule 1), std::regular only where the code needs operator==(T, T), since a carrier's == is one more operation of its signature. IsSpecies asks std::regular: a species' laws are equations, so its == belongs to it, and a function object with SpeciesTraits (std::logical_and<bool>) is an arrow, not a species (#1116).