syntax_data: {"ast_node_type":"other","tokens":[{"end":45,"kind":"keyword","start":0,"text":"sub_branch:"}]}
source_snippet:         sub_branch: MatchTreeSubBranch<'tcx>,
context_before:         &mut self,
context_after:         fake_borrows: &[(Place<'tcx>, Local, FakeBorrowKind)],