ABI Layer 3: no-resurrection (irreversibility) + determinism of consume#43
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Add Ephapaxiser.ABI.Semantics: a faithful model of single-use token state with the headline linearity property machine-checked. - Token (Fresh|Spent) with explicit consumed-state index. - Consumable t: proposition with NO constructor for the Spent (bad) case; Uninhabited (Consumable (spent token)) discharged by impossible clause. - Consumed before after: certificate of the unique Fresh -> Spent step. - consume: advances a Fresh token to Spent given Consumable evidence. - decConsumable: total, sound + complete Dec. - certifyConsume into the shared Result codes (Ok / AlreadyConsumed), with certifyConsumeSound (no believe_me) and certifySpentRejected. - Positive controls: freshTokenConsumable, consumeFreshSeven. - Negative control: spentTokenNotConsumable : Not (Consumable spent). Builds clean (exit 0, zero warnings). A deliberately false proof that a spent token is Consumable is rejected by idris2, confirming the property is non-vacuous. Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01A6PSzJWpRxtzGDjUCEh7Mx
Adds Ephapaxiser.ABI.Invariants over the existing Layer-2 Semantics model
(reuses Token/Consumable/Consumed/consume; no redefinition). Proves two
deeper, distinct properties of the single-use transition itself:
1. NO-RESURRECTION (irreversibility): the spent post-state of any Consumed
certificate is never Consumable (postStateNotConsumable). Transition
soundness — every reachable post-state is dead.
2. DETERMINISM (uniqueness): the certificate is unique for a given source/
target (consumedUnique), the result identity is single-valued
(consumeResultDeterministic), with a sound+complete Dec (decConsumedEq)
and identity-preservation round-trip lemmas.
Includes positive controls (concrete inhabited witnesses) and negative/
non-vacuity controls (no-resurrection refutation; distinct ids stay distinct).
No axioms: no believe_me/idris_crash/assert_total/postulate/asserted equalities.
Builds clean (exit 0, zero warnings); both deliberately-false adversarial
proofs rejected. Registered last in ephapaxiser-abi.ipkg.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01A6PSzJWpRxtzGDjUCEh7Mx
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Summary
Layer 3 (second, deeper invariant): proves no-resurrection (a
Spenttoken can never be shownFreshagain — irreversibility) and determinism of the single-use consume transition. Distinct from and deeper than the Layer-2 "Spent not Consumable" property.New module
Ephapaxiser.ABI.Invariants(imports the Layer-2Semanticsmodel). Positive + non-vacuity controls.Testing
Idris2 0.7.0
--build→ exit 0, zero warnings. Adversarial rejection confirmed.build/removed. Nobelieve_me/postulate/sorry.🤖 Generated with Claude Code
https://claude.ai/code/session_01A6PSzJWpRxtzGDjUCEh7Mx
Generated by Claude Code