ADR-A95: Quantification alternative bounds

Status: Accepted Date: 2026-09-25 (proposed), 2026-09-25 (accepted) Related: Quantification §9.2 (containment), §9.6 (conversion), ADR-A89 Unit: applied-ontology-readiness (AOR-16)

Context

A lending facility’s limit may be stated as USD 10 million or EUR 9 million, each figure authoritative in its own currency. A subscription may price a tier at 20 USD or 18 EUR. Neither statement implies an exchange rate, and converting one into the other would change the agreement. A qnt:Bound has one value, so today the limit is stated in one currency and a candidate in the other needs a contextual conversion the agreement never made.

Decision

1. qnt:alternativeBound (qnt:Bound → qnt:Bound) links a bound to another statement of the same limit. Alternatives share the bound’s onSpace, boundSense and boundClosure, and their values differ in qnt:inUnit. The relation is symmetric and not functional.
2. Comparison uses the matching statement. A candidate is compared with the bound, among the bound and its alternatives, whose unit is the candidate’s own. No conversion is performed. If none matches, the comparison is Undetermined with the reason qnt:NoBoundInUnit, even when a conversion is declared, since converting would substitute a rate the limit’s author did not choose.
3. Structure is checked in SHACL. A shape rejects alternatives on different spaces, senses or closures, and two alternatives in one unit.

Consequences

• Quantification takes a MINOR bump, with the ADR-A86 cascade.
• The Eligibility IR’s interval plan gains one set of required intervals per unit, and every backend selects the set by the candidate’s unit. This compiler work is part of the same slice (AOR-16).
• Examples: a facility limit in two currencies and a tier price in two currencies.