syntax_data: {"ast_node_type":"other","tokens":[{"end":62,"kind":"keyword","start":0,"text":"ExprKind::VarRef"}]}
source_snippet:             ExprKind::VarRef { id } => Ok(self.block_map[id]),
context_before:         parse_by_kind!(self, expr_id, _, "basic block",
context_after:         )