feat(MultiTapeTM): add tape redirection plumbing - #936
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Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
barni120400
reviewed
Sep 23, 2026
barni120400
reviewed
Sep 23, 2026
barni120400
reviewed
Sep 23, 2026
Replace `rw [show ... from Function.iterate_succ_apply' ..]` with a direct `rw [runFrom, Function.iterate_succ_apply', ← runFrom]` in the three proofs that previously relied on the removed `runFrom_succ_eq_step'` wrapper lemma. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
Restore the concise case-split proof used on main before Action.apply lost its blanket @[simp]: add Action.apply explicitly to the simp set in the `some q` case instead of manually unfolding via Prod.ext/Storage.ext. Verified this avoids the linter.flexible warning under --wfail --iofail. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
Adapt proofs to the new `Fin.append`/`Fin.natAdd`/`invOfMemRange`-based definitions of `inCfg` (InputFromTape) and `partialInv` (ExtendTapes): - Replace subtype literals `⟨k, by omega⟩`/`⟨k + 1, by omega⟩` with `Fin.natAdd k 0`/`Fin.natAdd k 1` throughout InputFromTape.lean to match the new definition's indexing. - Fix `inCfg_workTapes_vip`/`_flag` and `inCfg_workTapePos_vip`/`_flag`, which no longer reduced by `simp [inCfg]` alone under the `Fin.append` encoding (removes a leftover `sorry`). - Simplify `partialInv_isPartialInv` to use the dedicated `Function.Embedding.left_inv_of_invOfMemRange`/ `right_inv_of_invOfMemRange` lemmas instead of manually re-deriving them via `Fintype.choose_spec`, matching the new `invOfMemRange`-based `partialInv` definition. Verified with lake build --wfail --iofail, mk_all --check, lake test, lake lint, lake exe lint-style. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
crei
marked this pull request as ready for review
September 25, 2026 06:00
crei
requested review from
SamuelSchlesinger,
arademaker,
chenson2018,
fmontesi,
kim-em and
sorrachai
as code owners
September 25, 2026 06:00
… modifiers Add `runFrom_comm`, which lifts a step-semiconjugation to whole runs, and `spaceUsed_le_of_workTapePos_embedding`, which bounds the space of a simulation that tracks the original heads on embedded tapes. The run and space lemmas of `extendTapes`, `inputFromTape` and `outputToTape` become applications of these, and the step lemmas are shortened to a case split on the tape index followed by `simp`. `Action.apply` now derives its projection lemmas with `@[simps -fullyApplied]`, unused lemmas are removed, and the `inputFromTape` reading lemmas are public simp lemmas stated in terms of `inCfg`.
Restore `step_inputPos_of_state`, `step_workTapes_of_state`, `step_workTapePos_of_state`, `inputPos_runFrom_le` and `val_moveInputPos_le`, which later plumbing uses. Drop `runFrom_comm` in favour of `Function.Semiconj.iterate_right`, as leanprover#942 did, passing only the configuration map. `inputFromTape` builds its tape actions with `Fin.append` like `inCfg`, the space lemma takes its embedding as `e` with the hypothesis oriented like `spaceUsed_eq_of_workTapePos`, and `val_moveInputPos_sub_one` is renamed to `val_moveInputPos_sub_one_eq_clampMove`.
…pe-plumbing-refactor refactor(MultiTapeTM): simplify the tape redirection plumbing
SamuelSchlesinger
approved these changes
Sep 26, 2026
SamuelSchlesinger
enabled auto-merge
September 26, 2026 03:57
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This adds TM modifiers to use work tapes instead of input or output tapes