Pure syntactic shape: T closes strictly under the additive-group operator surface +, binary -, unary -. More...

Concept definition

template<typename T>
concept dedekind::algebra::HasGroupOperatorsAdd = 
    dedekind::category::IsClosedUnder<T, std::plus<>> &&
    dedekind::category::IsClosedUnder<T, std::minus<>> &&
    dedekind::category::IsClosedUnderUnary<T, std::negate<>>

Detailed Description

Pure syntactic shape: T closes strictly under the additive-group operator surface +, binary -, unary -.

Sibling of HasRingOperators (in :ring) restricted to the additive-group surface — the operators a callsite needs to spell group-theoretic translations of a + b, a - b, -a. Strict closure: each result is exactly T, not just convertible to T. Carriers that fail strict closure under literal + (e.g.\ bool, unsigned char, unsigned short — integer promotion to int) correctly refuse, matching the math-textbook stance the project adopts (#393).

Introduced under #394 as the additive-group companion of HasRingOperators / HasFieldOperators. A conjunction of category::IsClosedUnder, one operator each, so the shape subsumes every per-operator closure it names.