syntax_data: {"ast_node_type":"other","tokens":[{"end":37,"kind":"keyword","start":0,"text":"Ok(Rvalue::Aggregate("}]}
source_snippet:                 Ok(Rvalue::Aggregate(
context_before:                 let elem_ty = expr.ty.builtin_index().expect("ty must be an array");
context_after:                     Box::new(AggregateKind::Array(elem_ty)),