syntax_data: {"ast_node_type":"variable","tokens":[{"end":67,"kind":"keyword","start":0,"text":"let"}]}
source_snippet:         let block = parse_by_kind!(self, expr_id, _, "basic block",
context_before:     fn parse_block_def(&self, expr_id: ExprId, is_cleanup: bool) -> PResult<BasicBlockData<'tcx>> {
context_after:             ExprKind::Block { block } => &self.thir[*block],