ABI Layer 3: run is a left monoid action of the input stream (runAppend)#39
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Add Lustreiser.ABI.Semantics, raising the Idris2 ABI to Layer 2 with a machine-checked flagship proof of the repo headline (formally verified real-time embedded code via Lustre). Faithful model: a synchronous saturating bounded-counter Lustre node with Tick/Reset inputs, a static cap, and one-tick state memory; step/run give the synchronous execution semantics. Properties proven (no believe_me/postulate/assert): - Invariant preservation per tick: WithinBound c -> WithinBound (step i c) for every input, lifted to whole runs via runPreservesBound (no overflow). - Determinism (synchronous hypothesis): equal input streams from equal state yield equal output streams. - Sound+complete Dec (decWithinBound) + sound certifier (certifyBoundSound). - Positive controls (explicit witnesses, incl. a run that saturates) and a machine-checked negative control (overflowNotWithinBound) ensuring non-vacuity; a deliberately false witness is rejected by idris2. Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01A6PSzJWpRxtzGDjUCEh7Mx
…tInc monotonicity Adds Lustreiser.ABI.Invariants over the existing Semantics model (same Input/CounterNode/satInc/step/run). Proves a deeper, distinct class of property than the Layer-2 bound/cong-determinism: - FLAGSHIP: runAppend — run (xs ++ ys) c = run ys (run xs c), the monoid action / fold-fusion law, by genuine induction on the prefix (not cong). - Corollaries: runConsSplit, runResetClears, runEndingInResetIsZero (transition soundness consumed through runAppend). - ORTHOGONAL: satIncMonotone — order preservation of the saturating successor (m <= n => satInc cap m <= satInc cap n), plus stepTickMonotone. - decEqInput: sound+complete Dec for input equality. - Positive controls (appendWitness, resetSuffixWitness, monotoneWitness) and non-vacuity controls (prefixMatters, inputsDistinct, satIncNotConstant, all Not (...)). No believe_me/postulate/assert/idris_crash. %default total. Clean build, zero warnings; adversarial false-equality check rejected. 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
runis a left monoid action of the input stream on node state —runAppend : run (xs ++ ys) s = run ys (run xs s)— so streaming composes. Distinct from and deeper than the Layer-2 bound invariant.New module
Lustreiser.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