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> + > + // INVARIANT: `VECTOR` is within the widest supported tree. > + Self(VECTOR) > + } > + > + /// Returns the vector number. > + pub(super) const fn into_raw(self) -> u32 { > + self.0 > + } > + > + /// Returns the leaf that carries this vector. > + pub(super) fn leaf_index(self) -> LeafIndex { > + // By the type invariant the quotient is already below 16, so th= e mask changes nothing. It > + // is what proves the bound to `from_expr`. > + LeafIndex::from_expr(crate::num::u32_as_usize(self.0 / VECTORS_P= ER_LEAF) & LEAF_INDEX_MASK) Noticed this while reviewing patch 7. Another nice side effect of making `GinVector` a `Bounded` is that you can now get rid of this `from_expr` (which relies on the optimizer-dependent `build_assert!` under the hood) by doing `self.0.shr::<5, 4>()` (i.e. divide by 32, aka. VECTORS_PER_LEAF) and now you have... A `Bounded` that fits perfectly into a `LeafIndex`! This method then becomes: pub(super) fn leaf_index(self) -> LeafIndex { // CALC: `self.0 / VECTORS_PER_LEAF`. self.0.shr::<{ VECTORS_PER_LEAF.ilog2() }, _>().cast() } `LEAF_INDEX_MASK` is now unused and can be removed.