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给定以下基于 ggplot 的环境（最初来自：ggplot2: Multiple color scales or shift colours systemly on different layers?）

GeomBoxplotDark <- ggproto(ggplot2:::GeomBoxplot,expr={
                     draw <- function(., data, ..., outlier.colour = "black", outlier.shape = 16, outlier.size = 2) {
                       defaults <- with(data, {                               # ** OPENING "{" ADDED **
                         cols_dk <- rgb2hsv(col2rgb(colour)) - c(0, 0, 0.2)     # ** LINE ADDED        **
                         cols_dk <- hsv(cols_dk[1,], cols_dk[2,], cols_dk[3,])  # ** LINE ADDED        **
                         data.frame(x = x, xmin = xmin, xmax = xmax,
                                    colour = cols_dk,                                    # ** EDITED, PASSING IN cols_dk **
                                    size = size,
                                    linetype = 1, group = 1, alpha = 1,
                                    fill = alpha(fill, alpha),
                                    stringsAsFactors = FALSE
                         )})                                                    # ** CLOSING "}" ADDED **
                       defaults2 <- defaults[c(1,1), ]

                       if (!is.null(data$outliers) && length(data$outliers[[1]] >= 1)) {
                         outliers_grob <- with(data,
                                               GeomPoint$draw(data.frame(
                                                 y = outliers[[1]], x = x[rep(1, length(outliers[[1]]))],
                                                 colour=I(outlier.colour), shape = outlier.shape, alpha = 1,
                                                 size = outlier.size, fill = NA), ...
                                               )
                         )
                       } else {
                         outliers_grob <- NULL
                       }

                       with(data, ggname(.$my_name(), grobTree(
                         outliers_grob,
                         GeomPath$draw(data.frame(y=c(upper, ymax), defaults2), ...),
                         GeomPath$draw(data.frame(y=c(lower, ymin), defaults2), ...),
                         GeomRect$draw(data.frame(ymax = upper, ymin = lower, defaults), ...),
                         GeomRect$draw(data.frame(ymax = middle, ymin = middle, defaults), ...)
                       )))
                     }
  }
)

我想用以下函数调用它：

geom_boxplot_dark <- function (mapping = NULL, data = NULL, stat = "boxplot", position = "dodge", 
outlier.colour = "black", outlier.shape = 16, outlier.size = 2, 
...) 
GeomBoxplotDark$new(mapping = mapping, data = data, stat = stat, 
position = position, outlier.colour = outlier.colour, outlier.shape = outlier.shape, 
outlier.size = outlier.size, ...)

但是，在调用该函数时，它无法正确调用环境并给出以下错误：

> geom_boxplot_dark()
Error in geom_boxplot_dark() : attempt to apply non-function

有什么建议么？

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0 回答 0