syntax_data: {"ast_node_type":"variable","tokens":[{"end":49,"kind":"keyword","start":0,"text":"let"}]}
source_snippet:         let empty = self.bottom_value(self.body);
context_before:     fn mock_results(&self) -> IndexVec<BasicBlock, DenseBitSet<usize>> {
context_after:         let mut ret = IndexVec::from_elem(empty, &self.body.basic_blocks);