syntax_data: {"ast_node_type":"function","tokens":[{"end":56,"kind":"keyword","start":0,"text":"fn"}]}
source_snippet:     fn encode_crate_num(&mut self, crate_num: CrateNum);
context_before:     /// tcx. Therefore, make sure to include the context when encode a `CrateNum`.
context_after:     fn encode_def_index(&mut self, def_index: DefIndex);