syntax_data: {"ast_node_type":"variable","tokens":[{"end":65,"kind":"keyword","start":0,"text":"let"}]}
source_snippet:         let drop_and_continue_block = self.cfg.start_new_block();
context_before:         self.cfg.push_assign(block, source_info, discr, rvalue);
context_after:         let imaginary_target = self.cfg.start_new_block();