{"ast_node_type":"variable","tokens":[{"end":100,"kind":"keyword","start":0,"text":"if"}]}
        if let ExprKind::Struct(QPath::LangItem(LangItem::Range, ..), [range_start, range_end], _) =
        // I don't use 'is_range_literal' because only double-sided, half-open ranges count.
            last_expr_field.expr.kind