📐world-state-core-commands

The groupant beside world/src/world.rs in the Mova repository: what the code computes, what it never does, how to go back from its outputs, its invariants, cost and checks.

Facts

Components

Obernants

The typed relations around the forward model: the behaviour complement (what the code never does), the reverse reconstruction (every input compatible with an output) and specialised views.

Model text

Domain: finite in-memory values, successful allocation, parser-valid Cmd shapes and coherent imported registry/state metadata unless a fixture deliberately injects a mismatch. Neural parsing/model loading remains outside the domain; one fixed program exercises the deterministic change-language parser. Model status: source-derived partial relations, finite correspondence only. Unknown behavior is not excluded. Each named section defines its operator/observation; source identity and byte scopes are in manifests.

forward

exec stages per-entity ordered deltas in a BTreeMap transaction, creates one state per nonempty transaction entry in ID order, with latest+1 version and shared cause/note metadata. Cursor and events append directly to the temporary world. Loc/Obj/Char create attributes and inverse containment links; Cursor inherits omitted at/time. Move updates both containment sides; Have deliberately leaves the old side for post-link rejection; Give requires current holder, distinct recipient and nearness. Set rejects At, wrong keys and silent known-value changes, with v3 repeated-death identity checks. Rel creates/updates endpoints and fact sets, leaving obsolete links for validation. Event/Say capture participant versions and metadata. Plan/Believe maintain owner links and stage transitions; Done/Unset clear known fields with causes. Feel changes a tag collection under continuity/silent-change guards. Detach/Attach rewrite part/whole and containment links with nearness and real-cause checks. Mention only contributes touched IDs. Narrative-only commands return Frame here. Before flushing deltas, a cause's world/branch must match this world.

behavior_complement

Within parser-valid commands and coherent pre-worlds, exclude silently changing known Set fields without cause, transferring an object between characters through Move, self-Give, or committing staged changes caused by a mismatched world/branch. Other command paths remain source-reviewed rather than exhaustively verified.

reverse_reconstruction

For a committed state delta bundle, retain prior snapshots, command and cause combinations producing the ordered bundle. Repeated equal Set or same-location Move may leave no state; metadata and mentions distinguish histories that snapshots alone collapse. Recovering a full prior world requires old values unavailable from a forward Set delta.

transaction_grouping

Tx groups all deltas for one ID into one appended state, preserving operation order inside that state; final entity ordering follows BTreeMap. Atomicity is supplied by outer apply, not by exec. Direct cursor/event writes can precede later errors in a temporary world.

ownership_transition

A successful object Move from L to C removes L.Objects, sets O.At=C and adds C.Items; historical snapshots remain unchanged. Same destination emits no new delta/state. Have intentionally stages only new holder and object, so old-holder mismatch is rejected by check_links in public apply.

parser_preconditions

Say assumes a nonempty acts list, Plan assumes create or close shape, entity IDs/types/fields assume parser constraints beyond helper checks. Malformed hand-built Cmd can panic or bypass intended schema. Most tests construct valid commands directly; a fixed five-line change-language program additionally checks real parser-to-root-executor-to-snapshot wiring. Neither establishes general parser acceptance or narrative-root policy.

invariant

Fields follow last writes; sets are ordered unique IDs with empty sets removed after deletion. Versions are appended under the stated counter bounds. Public apply's Err preserves the caller; local mutations require that outer boundary. Inverse containment links hold only after successful checking, not for arbitrary injected worlds. All preimages retain ambiguity and shared intermediate state.

composition

Immediate children share the same Entity/Snap/World/Line values and source snapshot. Compose position -> clone -> local/narrative dispatch -> link checks -> mentions -> commit, retaining failure order and intermediate registry identity. Do not combine independent projection fibers as a Cartesian product. The file root additionally covers native test helpers and full-file glue. Story dispatch is a dependency, not a child claimed verified here.

cost

Let H be total stored deltas, P their payload bytes, N entities, E events and K inspected link entries. Snapshot replay costs its prefix deltas plus payload cloning and ordered-map operations. apply clones all retained world text/history/story state before dispatch; that cost cannot be omitted. check_links may repeatedly replay referenced histories, so a conservative bound counts O((N+K)*(H+P+log(N+1))) work plus ordered-set operations, not a linear cached-snapshot claim. need_event is O(E); next_free scans IDs. place has 17 admitted recursion levels; ancestors holds at most 65 IDs. run sums executed calls, cloning both accepted and subsequently rejected attempts. External Story work, allocation latency and formatting costs are unmeasured; no wall-clock or asymptotic bound for opaque dependencies is asserted.

checks

Six native wave7_world tests: 625 delta histories times five prefixes (3,125 snapshot/last-write/set-membership checks), 25 anchor pairs, staged ownership rollback and successful/no-op move, ordered mentions/cursor inheritance, spatial and registry projections, frozen event references and rejected-anchor coverage; a five-line parser/root-run join creates two locations and a character, moves it, rejects a missing location, then checks both historical and latest snapshots. Oracles use final-operation lookup and direct Boolean conditions rather than replaying the implementation. Broader command branches remain source-reviewed, not exhaustively tested. Evidence records repeated debug/release runs, a compiled production mutation and syntax identity.

epoch-memory

2026-10-30 initial epoch. Prospective expectations: last-operation oracle agrees with replay; temporary-world rejection leaves the original unchanged; no-op moves affect mentions but not versions. Review records clamped snapshot versions, parser-dependent Say/Plan invariants, missing-target default snapshots, nonvalidating location lookup, and coverage of rejected lines. No production semantics were changed. Preserve these boundaries in later modeling epochs; a new registry entry alone is not verification.

This page in Markdown → https://md.groupants.elamur.ai/free/en/mova/world/src/world.rs.groupant/commands.groupant/