Add examples to color functions

R/color.R

 #' @param strength The "strength" of the blend with white or black,
 #'   where 0 is entirely the original color and 1 is entirely white
 #'   (`lighten_color()`) or black (`darken_color()`).
+#' @examples
+#' blue <- "#0e6ba8"
+#' blue_light <- lighten_color(blue, strength = 0.33)
+#' blue_dark <- darken_color(blue, strength = 0.33)
+#'
+#' if (requireNamespace("scales", quietly = TRUE)) {
+#'   scales::show_col(c(blue_light, blue, blue_dark))
+#' }
+#'
 #' @name lighten_darken_color
 NULL
 
 #'   and appending to the hex color.
 #' @inheritParams lighten_darken_color
 #' @param opacity Desired opacity of the output color
+#' @examples
+#' blue <- "#0e6ba8"
+#' blue_transparent <- apply_alpha(blue)
+#'
+#' if (requireNamespace("scales", quietly = TRUE)) {
+#'   scales::show_col(c(blue, blue_transparent))
+#' }
+#'
 #' @export
 apply_alpha <- function(color_hex, opacity = 0.5) {
   paste0(color_hex, as.hexmode(round(255 * opacity, 0)))
 #' `substitute(darken_color(x, 0.8))`, if black text provides the best contrast.
 #' @param white Text or foreground color or expression, e.g. "#EEE" or
 #' `substitute(lighten_color(x, 0.8))`, if white text provides the best contrast.
+#' @examples
+#' light_green <- "#c4d6b0"
+#' contrast_green <- choose_dark_or_light(light_green)
+#' dark_purple <- "#381d2a"
+#' contrast_purple <- choose_dark_or_light(dark_purple)
+#'
+#' if (requireNamespace("scales", quietly = TRUE)) {
+#'   scales::show_col(c(light_green, contrast_green, dark_purple, contrast_purple))
+#' }
+#'
 #' @export
 choose_dark_or_light <- function(x, black = "#000000", white = "#FFFFFF") {
   if (is_light_color(x)) eval(black) else eval(white)

R/ggplot2.R

 #'
 #' @param setting A xaringanthemer style setting
 #' @inheritParams theme_xaringan
+#' @examples
+#' # Create a xaringanthemer style in a temporary file for this example
+#' xaringan_themer_css <- tempfile("xaringan-themer", fileext = ".css")
+#'
+#' style_solarized_light(outfile = xaringan_themer_css)
+#'
+#' theme_xaringan_get_value("text_color")
+#' theme_xaringan_get_value("background_color")
+#' theme_xaringan_get_value("header_color")
+#' theme_xaringan_get_value("text_bold_color")
+#'
 #' @export
 theme_xaringan_get_value <- function(setting, css_file = NULL) {
   requires_xaringanthemer_env(css_file = css_file)

man/apply_alpha.Rd

 converting opacity in the \verb{[0, 1]} range to hex in the \verb{[0, 255]} range
 and appending to the hex color.
 }
+\examples{
+blue <- "#0e6ba8"
+blue_transparent <- apply_alpha(blue)
+
+if (requireNamespace("scales", quietly = TRUE)) {
+  scales::show_col(c(blue, blue_transparent))
+}
+
+}

man/choose_dark_or_light.Rd

 Takes a color input as \code{x} and returns either the black or white color (or
 expression) if dark or light text should be used over the input color for
 best contrast. Follows W3C Recommendations.
+}
+\examples{
+light_green <- "#c4d6b0"
+contrast_green <- choose_dark_or_light(light_green)
+dark_purple <- "#381d2a"
+contrast_purple <- choose_dark_or_light(dark_purple)
+
+if (requireNamespace("scales", quietly = TRUE)) {
+  scales::show_col(c(light_green, contrast_green, dark_purple, contrast_purple))
+}
+
 }
 \references{
 \url{https://stackoverflow.com/a/3943023/2022615}

man/lighten_darken_color.Rd

 \description{
 Produces a linear blend of the color with white or black.
 }
+\examples{
+blue <- "#0e6ba8"
+blue_light <- lighten_color(blue, strength = 0.33)
+blue_dark <- darken_color(blue, strength = 0.33)
+
+if (requireNamespace("scales", quietly = TRUE)) {
+  scales::show_col(c(blue_light, blue, blue_dark))
+}
+
+}

man/theme_xaringan_get_value.Rd

 }
 }
 
+\examples{
+# Create a xaringanthemer style in a temporary file for this example
+xaringan_themer_css <- tempfile("xaringan-themer", fileext = ".css")
+
+style_solarized_light(outfile = xaringan_themer_css)
+
+theme_xaringan_get_value("text_color")
+theme_xaringan_get_value("background_color")
+theme_xaringan_get_value("header_color")
+theme_xaringan_get_value("text_bold_color")
+
+}