{"ast_node_type":"variable","tokens":[{"end":79,"kind":"keyword","start":0,"text":"let"}]}
        let u8 = self.cx.path_ident(self.span, Ident::new(sym::u8, self.span));
    fn ptr_u8(&self) -> P<Ty> {
        let ty_u8 = self.cx.ty_path(u8);