The variable-link Widget

Syntax:

type ::= (variable-link [keyword argument]...  var)

A widget to represent a link to an Emacs variable. Its super is the link widget.

It overrides the :action property, to a function to describe var.

Example:

(widget-create 'variable-link
               :button-prefix ""
               :button-suffix ""
               :tag "What setting controls button-prefix?"
               'widget-button-prefix)