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Dedekind 0.0.0
A structuralist C++23 Module Library
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Cardinality class of a halfspace's carrier T (#848/#927).
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Public Types | |
| using | type |
Cardinality class of a halfspace's carrier T (#848/#927).
A carrier that declares its own cardinality_type is the authority (e.g. numbers::Rational → ℵ_0, ExtensionalCardinal → Finite): this partition (:order) is upstream of :numbers, so a countable non-integral carrier such as ℚ cannot be recognised structurally here (IsRingIntegral is false on Rational), and must self-declare so the point-free A|pred halfspace classifies identically to the scout comprehension (which inherits the ambient C directly). Otherwise fall back to the IsRingIntegral discriminator: the structural integers and the Cardinality / SignedCardinality (ℕ/ℤ) proxies are ℵ_0, and the real proxies (QuadraticReal, double) are the continuum ℶ_1. The bound only has to be tight enough for the countability verdict (IsCountable).
| using dedekind::order::carrier_cardinality< T >::type |