Expand description
The Architect’s term language — flat, multi-arity, Copy.
Children are NodeIds (e-class references after canonicalization).
Var carries (symbol index, version) — versions partition reads of a
mutable name so equality never leaks across a write. Opaque is the
escape hatch: any expression the e-graph does not model (calls, indexing,
collection literals, text) becomes an opaque leaf whose ORIGINAL &Expr
pointer is held by the converter, so extraction reproduces it verbatim —
effects and error behavior preserved by construction.