{"ast_node_type":"impl","tokens":[{"end":68,"kind":"keyword","start":0,"text":"discr_range_of_repr:"}]}
        discr_range_of_repr: impl Fn(i128, i128) -> (Integer, bool),
        variants: &IndexSlice<VariantIdx, IndexVec<FieldIdx, F>>,
        discriminants: impl Iterator<Item = (VariantIdx, i128)>,