At every moment the text terminal is configured to use certain foreground and background colors. Initially, these are the default colors, which depend on the underlying terminal capabilities, and maybe also on some system wide configuration setting.
Terminal colors are encoded in triplets of integers signifying RGB
colors, i.e. levels of beams for red, green and blue. These
triplets are implemented as values of type int<32>[3].
The special value [-1, -1, -1] means the default color, for
both foreground and background. There are two predefined variables
for this:
var term_default_color = [-1,-1,-1]; var term_default_bgcolor = [-1,-1,-1];
Getting and setting the foreground and background colors is performed
using the term_get_color, term_set_color,
term_get_fgcolor and term_set_fgcolor functions, with
signatures:
fun term_get_color = int<32>[3] fun term_set_color = (int<32>[3] color) void fun term_get_bgcolor = int<32>[3] fun term_set_bgcolor = (int<32>[3] color) void