)    if (length(methods) == 1L)         return(methods[[1L]])    else if (length(methods) == 0L) {        cnames &lt;- paste0("\"", vapply(classes, as.character,             ""), "\"", collapse = ", ")        stop(gettextf("unable to find an inherited method for function %s for signature %s",             sQuote(fdef@generic), sQuote(cnames)), domain = NA)    }    else stop("Internal error in finding inherited methods; didn't return a unique method",         domain = NA)})(list("NULL", "character", "tbl_df")