syntax_data: {"ast_node_type":"other","tokens":[{"end":52,"kind":"keyword","start":0,"text":"#[allow(rustc::potential_query_instability)]"}]}
source_snippet:         #[allow(rustc::potential_query_instability)]
context_before:     fn extend_from_child(&mut self, step_kind: PathKind, nested_goals: &NestedGoals<X>) {
context_after:         for (input, paths_to_nested) in nested_goals.iter() {