Using ggsave with a pipe - r

Question

I can save a plot with ggsave after I stored it, but using it in a pipeline I get the following error. I wish to plot and save in the same (piped) command.
no applicable method for 'grid.draw' applied to an object of class "c('LayerInstance', 'Layer', 'ggproto', 'gg')"
I know ggsave's arguments are first the filename, and then the plot, but switching this in a wrapper does not work. Also, using 'filename=' and 'plot=' in the ggsave command does not work.
library(magrittr)
library(ggplot2)
data("diamonds")
# my custom save function
customSave <- function(plot){
ggsave('blaa.bmp', plot)
}
#This works:
p2 <- ggplot(diamonds, aes(x=cut)) + geom_bar()
p2 %>% customSave()
# This doesn't work:
ggplot(diamonds, aes(x=cut)) + geom_bar() %>% customSave()
# and obviously this doesn't work either
ggplot(diamonds, aes(x=cut)) + geom_bar() %>% ggsave('plot.bmp')

Answer 1

As akrun pointed out, you need to wrap all of your ggplot in parentheses. You can also use the dot notation to pass an object to a function parameter other than the first in a magrittr pipe stream:
library(magrittr)
library(ggplot2)
data("diamonds")
(
ggplot(diamonds, aes(x=cut)) +
geom_bar()
) %>%
ggsave("plot.png", . , dpi = 100, width = 4, height = 4)

Answer 2

Update: The following code no longer works. See the tidyverse GitHub issue and another StackOverflow question for the official solution.
Original answer that NO LONGER WORKS:
If you want to plot and save in one line, try this
ggsave('plot.bmp') ```
If you don't want to show the plot, simply put `p <- ` at the
beginning.
If you have a custom save function, you can also do this
``` mysave <- function(filename) { ggsave(file.path("plots",
paste0(filename, ".png")),
width = 8, height = 6, dpi = 300) } ```
and simply replace `ggsave('plot.bmp')` with `mysave('plot')` in the
snippet above.
I found this usage by accident but haven't found any documentation.