Constraints: boundaries

What the construct does NOT do in 0.2: limits, closed lists, neighbouring constructs, and the selection rule.

OverviewBoundariesCorpus formsPitfalls

Does not do

• Does not infer. Adds no logical support, takes no part in defeat/priority as a rule. X only_if Y never infers Y.
• Does not sanction. Creates no automatic legal violation/sanction: failure is a validation/compliance finding. A sanction is a separate rule on established facts.
• Does not substitute for a position. A finding has no holder, window, or lifecycle: position pending/active/satisfied/violated do not apply here; the verdicts are its own — satisfied/violated/ conflicted/undetermined.
• Does not aggregate secretly. The v1 aggregation query policy is one — all: findings are neither hidden nor folded. severity affects only the issue record, not the verdict.
• Does not apply outside its window. With effective outside the law date the constraint does not apply; an unexecutable one declares NON_EXECUTABLE_CONSTRAINT and is not evaluated.

Reserved and closed

• fatal as a schema severity is reserved for computation halt: critical on a constraint is written as error with details.severity = "critical".
• A constraint’s message enters the issue as constraint <id> <verdict>: <message>; without message the defaults are plain “requirement not met” / “antecedent or requirement contradictory”.
• The issue-blocking scope: error blanks only a result depending on the predicates of this constraint’s scope/when/require clauses; the constraint verdict and result themselves are unchanged.

Neighbours and selection rule

• constraint vs rule: coherence checking without inference vs consequent inference with support. Want Y established — a rule.
• constraint vs prohibition: a finding without holder or window vs a norm with holder, window, and lifecycle. Someone to refrain and a when — a prohibition. See the prohibitions page.
• constraint vs definition necessary: a one-off check vs a concept half with the was_derived_from provenance edge. See the definitions page.
• require vs valid_when: a check without effect vs an exercise validity condition with POWER_INVALID_EXERCISE. See the powers page.
• only_if vs if X then Y: always a constraint vs a rule, only if Y is an admissible head (a literal or a norm template).