Function mz_transform::normalize_lets::renumbering::renumber_bindings

pub fn renumber_bindings(
    relation: &mut MirRelationExpr,
    id_gen: &mut IdGen,
) -> Result<(), TransformError>

Re-assign an identifier to each Let.

Under the assumption that id_gen produces identifiers in order, this process maintains in-orderness of LetRec identifiers.