Brummel
2769e50a35
Final iteration of spec 0064 (the #55-cutover hardening, #57). Closes class 4, the one genuine corpus bug among the four (not a false positive): std_either_list.partition_eithers projected both (app Pair.fst rest) and (app Pair.snd rest) from one owned `rest`. Pair.fst/snd are own-param projections that move a field out, so each consumes `rest` -> a genuine double-consume that universal linearity activation (#55) would correctly reject. The fix is a body rewrite (destructure `rest` once via (match rest (case (pat-ctor MkPair ls rs) …)) then dispatch on the head), NOT a check change -- the check is right. Latent until activation: partition_eithers' param is a bare (Implicit) slot today, so the check is skipped on it -- no RED->GREEN flip on the real fixture. The rewrite is a pre-emptive corpus fix. Its correctness rests on the unchanged 2 3 2 3 E2E output (std_either_list_demo, a semantically-identical partition) and on the new c4_double_consume must-stay-RED fixture, which -- with explicit modes, so the check is active today -- demonstrates the double-projection shape IS rejected. - examples/std_either_list.ail: partition_eithers Cons arm rewritten; doc updated (destructure-once, no longer "projections"). - examples/c4_double_consume.ail: must-stay-RED pin (the rejected shape), folded into a generalised harden_ownership_heap_double_consume_still_errors loop over {real_consume, c4_double_consume}. - examples/c4_rewrite.ail: stays-clean pin (the accepted destructure-once shape), added to harden_ownership_false_positives_are_clean. No hash-pin on std_either_list (verified); the e2e 2 3 2 3 output pin is the content pin and is preserved. No check/schema/codegen change. Verified: std_either_list checks clean; demo 2 3 2 3; both harden assertions green; cargo test --workspace green; bench/check.py 34/34, compile_check.py 24/24 stable. This is the last of the four #57 hardening classes. Spec 0064 is now code-complete: classes 1 (local fn-param modes), 2 (let-alias redirect), 3 (value-typed let-binder), and 4 (this) all shipped. The cycle is ready for audit; the #55 cutover precondition is met. refs #57