{"ast_node_type":"variable","tokens":[{"end":92,"kind":"keyword","start":0,"text":"let"}]}
            let field_op = ecx.project_field(&down, FieldIdx::from_usize(i)).discard_err()?;
        .map(|i| {
            let val = op_to_const(&ecx, &field_op, /* for diagnostics */ true);