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In that case, can we make the if arms symmetric: > > if let Some(sum) =3D addr.checked_add(PAGE_SIZE - 1) { > Some(sum & PAGE_MASK); > } else { > None > } Early return style makes the happy path less indented and is more consistent with the C side. However, here the happy case would be the indented case, so `let else` would be better: let Some(sum) =3D addr.checked_add(PAGE_SIZE - 1) else { return None; }; Some(sum & PAGE_MASK) Cheers, Miguel