avoid adding scales before initial

  }

  df <- .set_position(df)

  p <- ggplot(data = source_data) + ggplot2::theme_void()

  gs <- options("linkET.pairs.plot")$linkET.pairs.plot$scale

  scale <- list(NULL)

  if (!is.null(gs) && !length(gs) < 1) {

    mp <- mapping[intersect(names(mapping), c("fill", "colour", "size", "alpha", "shape"))]

    if (length(mp) > 0) {

                   function(x) { if (is_binary(source_data[[x]])) "d" else "c"},

                   character(1))

      ls <- gs[paste(names(tp), unname(tp), sep = "_")]

      p <- Reduce("+", gs[paste(names(tp), unname(tp), sep = "_")], init = p)

      scale <- gs[paste(names(tp), unname(tp), sep = "_")]

    }

  }

  df$.plot <- lapply(seq_len(nrow(df)), function(ii) {

    mapping2 <- aes_string(x = df$.colnames[ii], y = df$.rownames[ii])

    p$mapping <- aes_modify(mapping, mapping2)

    p

    mapping <- aes_modify(mapping, mapping2)

    p <- ggplot(data = source_data, mapping = mapping) + ggplot2::theme_void()

    Reduce("+", scale, init = p)

  })

  id <- vapply(source_data, function(x) is.factor(x) || is.character(x) || is.numeric(x),