Dynamic Array Runtime

Scope

Dynamic-array semantics cover:

• array literals
• spill allocation
• spill blocking
• scalar-vs-array argument behavior
• visible #SPILL! and related array errors

Runtime contract

• the engine must know which cell owns a spill
• blocked spill targets must produce Excel-style visible errors
• array-producing functions must preserve shape through recalculation and copy/fill
• WASM production routing for dynamic-array families requires array value transport, not scalar-only lowering

Dependency order

Dynamic arrays depend on:

• workbook metadata model
• richer runtime value model
• parser support for spill operators and array syntax

Exit gate

• SEQUENCE/FILTER/UNIQUE-class behavior is fixture-covered and production-routed through WASM