Brummel
5228542bfd
Cycle 0005 (BLOCKER #1): a node's output generalizes from one scalar to a record of K >= 1 named base-scalar columns, with a scalar being the degenerate K = 1 case. A node keeps exactly one output port; its payload is now an ordered bundle of base columns (a composite stream, C7). This unblocks every multi-column producer the engine needs next -- OHLCV bars and, later, the C10 position-event table -- none of which could exist while a node emitted at most one column. Revises C8, sharpens C7 in the design ledger. Contract (aura-core): - `NodeSchema.output: ScalarKind` -> `Vec<FieldSpec>` (FieldSpec = { name: &'static str, kind }; the field position is what an Edge binds, the name is metadata for later sinks/playground, C18). - `Node::eval -> Option<Scalar>` -> `-> Option<&[Scalar]>`: a node fills a buffer it owns (sized once at construction) and returns a borrowed K-field row; `None` still means filter/not-warmed. This is the C7-faithful representation chosen with the user: zero per-cycle heap allocation on the forward path (rejected: Option<Vec<Scalar>> allocates per fire; an inline fixed [Scalar; N] bakes a width cap; engine-owned output columns invert the eval model). Scalar output is the degenerate 1-field record -- no separate scalar path. Field-wise binding (aura-engine): - `Edge` gains `from_field: usize` -- which producer column this edge forwards. Consuming a whole record is N edges; there is no "bind whole record" mechanism. - bootstrap kind-checks per field (`from.output.get(from_field)` -> BadIndex if out of range; `field.kind != slot.kind` -> KindMismatch). - the run loop copies a producer's returned row into one reused scratch buffer (resolving the borrow; no per-cycle alloc once warm) and scatters scratch[from_field] into each out-edge slot. `NodeBox.out_len` (set at bootstrap) backs a debug_assert on the returned row width. `run` returns `Vec<Option<Vec<Scalar>>>` (the observed node's full row per cycle -- a materialization-surface alloc, not the inter-node hot path). - the K fields of one record are co-fresh by construction (one eval, one timestamp), so C6 is untouched. aura-std: Sma/Sub migrate to the 1-field degenerate case (hold a [Scalar; 1] buffer; behaviour unchanged). Sub drops #[derive(Default)] (Scalar has no Default) for a manual Default. Proof (aura-engine tests, +5): an Ohlcv 5-field bundler fed by five timestamp-aligned barrier sources emits one complete bar per timestamp (ohlcv_bundles_five_field_record); a downstream Sub binds high(1)-low(2) field-wise, observed end-to-end + a determinism re-run (edge_binds_single_field_high_minus_low); a second consumer binds close(3)-open(0) on the same record (distinct_edges_read_distinct_fields); must-fail: bootstrap_rejects_from_field_out_of_range (BadIndex), bootstrap_rejects_per_field_kind_mismatch (a TwoField [f64,i64] producer, the i64 field into an f64 slot). All prior 0003/0004 tests adapted to from_field + the Vec return, expected vectors unchanged (scalar = 1-field record). Gates re-run by the orchestrator (not just the agent): cargo build/test --workspace --all-targets (36: aura-core 19 + aura-std 3 + aura-engine 14, 0 failed) / clippy --workspace --all-targets -D warnings clean; surface-purity grep (no dyn-Any / Rc / RefCell) clean. Ledger C8/C7 edits verified (Option<&[Scalar]> present, "one series per node" gone, cycle-0005 realization note added). The glossary composite/node record-reality pass is the audit-time follow-up. closes #1 refs walking-skeleton Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>