syntax_data: {"ast_node_type":"variable","tokens":[{"end":73,"kind":"keyword","start":0,"text":"let"}]}
source_snippet:             let paths_to_nested = paths_to_nested.extend_with(step_kind);
context_before:         for (input, paths_to_nested) in nested_goals.iter() {
context_after:             self.insert(input, paths_to_nested);