Theming

Styling in a theming is provided by a use of a AttributedString from JLine. Unfortunately styling in JLine is mostly undocumented but we try to go through some of its features here.

In JLine a style spec is a string having a special format. Spec can be given multiple times if separated by a comma. A spec will either define a color for foreground, background or its mode. Special format <spec>:=<spec> allows to define a default within latter spec if former for some reason is invalid.

If spec contains a colon its former part indicates either foreground or background and possible values are foreground, fg, f, background, bg, b, foreground-rgb, fg-rgb, f-rgb, background-rgb, bg-rgb or b-rgb. Without rbg a color value is name from an allowable colors black, red, green, yellow, blue, magenta, cyan or white. Colors have their short formats k, r, g, y, b, m, c and w respectively. If color is prefixed with either ! or bright-, bright mode is automatically applied. Prefixing with ~ will resolve from JLine internal bsd color table.

If rgb format is expected and prefixed with either x or # a normal hex format is used.

If spec contains special names default, bold, faint, italic, underline, blink, inverse, inverse-neg, inverseneg, conceal, crossed-out, crossedout or hidden a style is changed accordingly with an existing color.

If spec is a number or numbers separated with semicolon, format is a plain part of an ansi ascii codes.