Function eq_element 

pub fn eq_element(a_bits: u64, b_bits: u64, elem_type: V2ElemType) -> bool

Per-kind value equality for the (bits, kind) carrier shape.

Returns true iff (a_bits, kind) and (b_bits, kind) denote the same value under the kind’s semantics. Returns false when either pointer is null for a heap-element kind (defensive — the dispatch shell rejects null receivers earlier, but the primitive must stay sound under any input).

Float semantics: bitwise equality (NOT ==). This is the IEEE-754-pure choice — NaN == NaN is false under == but true under bitwise compare. The choice matches the includes / indexOf observable: a NaN element pushed into the array IS findable via the same NaN bit pattern (the array doesn’t lose track of its own elements). The user can still write a custom predicate via find(|x| x != x) when IEEE compare is desired.

String / Decimal: deref through the v2-raw StringObj / DecimalObj carrier and compare content (StringObj::as_str → &str equality; DecimalObj::value → Decimal PartialEq).

TypedObject: deep field-by-field comparison. The two objects are equal iff (a) they share the same schema_id, (b) they share the same per-field NativeKind table, and (c) every per-field slot compares equal under the slot’s NativeKind via a recursive eq_element call on the slot bits. Per ADR-006 §2.7.16 typed-Arc dispatch-label receiver-recovery: the comparison reads the storage directly via &*(p as *const TypedObjectStorage) (no Box-wrap reinterpret).

Safety

The caller must uphold the §2.7.5 producer-side stamp invariant — for heap-element kinds (StringV2 / DecimalV2 / Ptr(HeapKind::TypedObject)), the bits must be either 0 (null) or a live carrier pointer of the matching T. The bits == 0 early-out is the defensive bound; otherwise the deref is sound under the construction-side contract upheld by every producer in this module.