syntax_data: {"ast_node_type":"variable","tokens":[{"end":96,"kind":"keyword","start":0,"text":"let"}]}
source_snippet:     let mut storage_live = MaybeStorageLive::new(std::borrow::Cow::Borrowed(always_live_locals))
context_before:     // lifetimes.
context_after:         .iterate_to_fixpoint(tcx, body, None)