syntax_data: {"ast_node_type":"variable","tokens":[{"end":59,"kind":"keyword","start":0,"text":"let"}]}
source_snippet:             let src_layout = into_layout(src_alts.clone());
context_before:         for src_alts in alts.clone().into_iter().powerset() {
context_after:             let src_set = into_set(src_alts.clone());