Create a style, or a style function, or both. This function
is intended for those who wish to use 256 ANSI colors,
instead of the more widely supported eight colors.
The style to create. See details and examples below.
bg
Whether the color applies to the background.
grey
Whether to specifically create a grey color.
This flag is included, because ANSI 256 has a finer color scale
for greys, then the usual 0:5 scale for R, G and B components.
It is only used for RGB color specifications (either numerically
or via a hexa string), and it is ignored on eigth color ANSI
terminals.
colors
Number of colors, detected automatically
by default.
Details
The crayon package comes with predefined styles (see
styles for a list) and functions for the basic eight-color
ANSI standard (red, blue, etc., see crayon).
There are no predefined styles or style functions for the 256 color
ANSI mode, however, because we simply did not want to create that
many styles and functions. Instead, make_style can be
used to create a style (or a style function, or both).
There are two ways to use this function:
If its first argument is not named, then it returns a function
that can be used to color strings.
If its first argument is named, then it also creates a
style with the given name. This style can be used in
style. One can still use the return value
of the function, to create a style function.
The style (the code... argument) can be anything of the
following:
An R color name, see colors().
A 6- or 8-digit hexa color string, e.g. #ff0000 means
red. Transparency (alpha channel) values are ignored.
A one-column matrix with three rows for the red, green
and blue channels, as returned by col2rgb (in the base
grDevices package).
make_style detects the number of colors to use
automatically (this can be overridden using the colors
argument). If the number of colors is less than 256 (detected or given),
then it falls back to the color in the ANSI eight color mode that
is closest to the specified (RGB or R) color.
See the examples below.
Value
A function that can be used to color strings.
See Also
Other styles: drop_style
Examples
## Create a style function without creating a style
pink <- make_style("pink")
bgMaroon <- make_style(rgb(0.93, 0.19, 0.65), bg = TRUE)
cat(bgMaroon(pink("I am pink if your terminal wants it, too.\n")))
## Create a new style for pink and maroon background
make_style(pink = "pink")
make_style(bgMaroon = rgb(0.93, 0.19, 0.65), bg = TRUE)
"pink" %in% names(styles())
"bgMaroon" %in% names(styles())
cat(style("I am pink, too!\n", "pink", bg = "bgMaroon"))