{"ast_node_type":"variable","tokens":[{"end":53,"kind":"keyword","start":0,"text":"let"}]}
        let suffix = Some(ast::UintTy::Usize.name());
    pub fn expr_usize(&self, span: Span, n: usize) -> P<ast::Expr> {
        let lit = token::Lit::new(token::Integer, sym::integer(n), suffix);