Button Label Normalization

Hyperbole uses a normalized form of button labels called button keys (or label keys) for all internal operations. See the documentation for the function (hbut:label-to-key) for details of the normalization process. The normalized form permits Hyperbole to recognize buttons that are the same but whose labels appear different from one another, due to text formatting conventions. For example, all of the following would be recognized as the same button.

  <(fake button)>     <( fake      button)>

  Pam>  <(fake
  Pam>    button)>

  ;; <(fake
  ;;   button)>

  /* <( fake      */
  /*    button )> */

The last three examples demonstrate how Hyperbole ignores common fill prefix patterns that happen to fall within the middle of a button label that spans multiple lines. As long as such buttons are selected with point at a location within the label’s first line, the button will be recognized. The variable hbut:fill-prefix-regexps holds the list of fill prefixes recognized when embedded within button labels. All such prefixes are recognized (one per button label), regardless of the setting of the Emacs variable, fill-prefix, so no user intervention is required.