syntax_data: {"ast_node_type":"other","tokens":[{"end":79,"kind":"keyword","start":0,"text":"ExprKind::Adt(box"}]}
source_snippet:             ExprKind::Adt(box AdtExpr { variant_index, fields, base, .. }) => {
context_before:         let constant = match &expr.kind {
context_after:                 assert!(matches!(base, AdtExprBase::None));