syntax_data: {"ast_node_type":"variable","tokens":[{"end":42,"kind":"keyword","start":0,"text":"let"}]}
source_snippet:         let repr = ReprOptions::default();
context_before:         let fields = tys.iter().map(|ty| cx.layout_of(*ty)).try_collect::<IndexVec<_, _>>()?;
context_after:         map_layout(cx.calc.univariant(&fields, &repr, kind))