syntax_data: {"ast_node_type":"other","tokens":[{"end":51,"kind":"keyword","start":0,"text":"//"}]}
source_snippet:     // and has no `super_fold_with` method to call.
context_before:     // The default region folder is a no-op because `Region` is non-recursive
context_after:     fn try_fold_region(&mut self, r: I::Region) -> Result<I::Region, Self::Error> {