A Property Kind Calculus for Measurement Metrology

17.3. The license clause — side conditions do not transfer🔗

A relation's license clause is the part of its declaration that extends its witness beyond the carrier rung the witness is proved at: one entry per further rung of the carrier ladder, each naming how the claim holds there — a repair theorem, or an independent witness restated at that rung.

Definition17.3.1
Group: The interface clause and the judgments on it. A boundary is declared , so a membership choice can be wrong about it — and the two decidable comparisons below are exactly the two ways it can be wrong: not the boundary the members compute, or not a faithful deployment of the tier below. (3)
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Definition 17.1.1
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Theorem 15.6.5
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used by 1✓L∃∀N

One rung of a relation's license clause: the carrier rung the claim is extended to, and how it holds there. Laws transfer across the carrier ladder at the cost of one rounding step per join; side conditions do not — a nonzero-total hypothesis checked over the reals constrains the exact total, over binary32 the rounded fold, and neither implies the other. So a relation claimed beyond the rung its witness is stated at owes, per additional rung, either a named repair — exact, where rounding is the identity on the values in play, or nonneg, where nonnegative on-grid weights rule the cancellation out — or restated: an independent witness proved at that rung. A rung claimed with no repair and no restatement is refused, because a side condition does not transfer by being assumed to.

Lean code for Definition17.3.1●1 definition
  • structure(2 fields)defined in PropertyKindCalculus/Provenance.lean
    complete
    structure PropertyKindCalculus.Provenance.RelationLicense : Type
    structure PropertyKindCalculus.Provenance.RelationLicense :
      Type
    One rung of a relation's license clause: the carrier rung the claim is extended to,
    spelled as the ladder names it (`ℝ`, `FP32`, `Float`, …), and how the claim holds there.
    A relation with an empty license list is stated at its witness's own rung and claims
    nothing beyond it; each entry here is one further rung, answered for by name. 
    rung : String
    The carrier rung, as the ladder names it. 
    transfer : PropertyKindCalculus.Provenance.TransferStatus
    How the claim holds at this rung: transferred by a named repair, or restated by a
    named per-rung witness. 
Proof for Definition 17.3.1
uses 0

A rung name and a three-constructor transfer status, each constructor carrying the name of its evidence; the elaborator checks the named evidence is a sorry-free theorem, and the refusal of an unanswered rung is a pinned probe.