{"ast_node_type":"other","tokens":[{"end":50,"kind":"keyword","start":0,"text":"$($(AstFragment::$Kind(ast)"}]}
                    $($(AstFragment::$Kind(ast) =>
                    $($(AstFragment::$Kind(ast) => vis.$mut_visit_ast(ast),)?)*
                        ast.flat_map_in_place(|ast| vis.$flat_map_ast_elt(ast, $($args)*)),)?)*