syntax_data: {"ast_node_type":"variable","tokens":[{"end":58,"kind":"keyword","start":0,"text":"let"}]}
source_snippet:             let target_block = self.cfg.start_new_block();
context_before:             // the drop order for the first sub-branch, we lower sub-branches in reverse (#142163).
context_after:             for (pos, sub_branch) in branch.sub_branches.into_iter().rev().with_position() {