The full-Score snapshot side of the three schema-major-1 data-model fields,
on a struct-level frozen v0 decoder. Snapshot-only: the CreateRegion op
payload stays byte-v0 (D2 owns the op-block migration + read-only).
Data model (epiphany-core):
- PitchRange { lowest, highest: Pitch } in pitch.rs; contains() is frame-guarded
(decides only within a shared PitchSpaceId) and treats a reversed range as
undecidable (None), not "everything out of range".
- Instrument.range: Option<PitchRange>; Region.permits_spanning_slurs: bool.
Codec:
- struct_codec! for PitchRange; Instrument -> {id,name,range}; Region appends
permits_spanning_slurs.
- Replaced the Phase-C byte-splice with a struct-level decode_v0_score: a
hand-written 19-field Score walk using dec_canvas_v0/dec_region_v0/
dec_instruments_v0 for the two changed fields (nested in Vecs) and the current
Codec for the other 17. Removed the now-unused Reader::pos().
- Region.canonical_bytes_v0() (+ enc_region_v0) is the frozen v0 op-payload
surface: CreateRegionOp embeds it so the op-envelope block stays byte-v0.
Advisory preconditions (epiphany-ops/validate.rs):
- PitchOutsideInstrumentRange: pitch-in-range via voice->instance->staff->
instrument (honoring instrument_override); "if any"/indeterminate-frame pass.
- Slur-spanning suppressed only when BOTH endpoint regions permit (AND
semantics; documented pending spec ratification of which region governs).
Tests: the three frozen-decoder fixtures (non-default v1 round-trip; a mirror
v0 encoder synthesizing genuine v0 bytes that migrate default-filling all three
fields, anchored by an independent byte-length check; the nested-Vec multi-
region case); the byte-v0 CreateRegion payload; the frame-aware/reversed-range
contains(); and 5 advisory tests. ~29 construction sites updated. Full gate
green (workspace tests, clippy -D warnings, fmt, rustdoc -D warnings).
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01NEs4aYiu8MXjdYdMxw8PTd
Levi Neuwirth
03758bbae0