syntax_data: {"ast_node_type":"variable","tokens":[{"end":56,"kind":"keyword","start":0,"text":"let"}]}
source_snippet:             let next_block = self.cfg.start_new_block();
context_before:             // If `candidate` has become a leaf candidate, ensure it has a `pre_binding_block` and `otherwise_block`.
context_after:             candidate.pre_binding_block = Some(next_block);