Variable: whitespace-tab-regexp

whitespace-tab-regexp is a customizable variable defined in whitespace.el.gz.

Value

"\\(	+\\)"

Documentation

Regexp to match TAB characters that should be visualized.

The TAB characters are highlighted using the whitespace-tab face. By default only ASCII TAB character is visualized, but if you are typing in some non-Latin language, there may be other characters besides " " that should be considered a TAB.

Here are some examples:

   "\\\\(^\\t+\\\\)" visualize only leading TABs.
   "\\\\(\\t+$\\\\)" visualize only trailing TABs.
   "\\\\(^\\t+\\\\|\\t+$\\\\)" visualize leading and/or trailing TABs.
   " \\\\(\\t+\\\\) " visualize only TABs between SPACEs.

NOTE: Always enclose the elements to highlight in \\(...\\).
      Use exactly one pair of enclosing \\( and \\).

This variable is used when whitespace-style includes tabs.

Source Code

;; Defined in /usr/src/emacs/lisp/whitespace.el.gz
(defcustom whitespace-tab-regexp "\\(\t+\\)"
  "Regexp to match TAB characters that should be visualized.

The TAB characters are highlighted using the `whitespace-tab' face.
By default only ASCII TAB character is visualized, but if you
are typing in some non-Latin language, there may be other
characters besides \" \" that should be considered a TAB.

Here are some examples:

   \"\\\\(^\\t+\\\\)\"		visualize only leading TABs.
   \"\\\\(\\t+$\\\\)\"		visualize only trailing TABs.
   \"\\\\(^\\t+\\\\|\\t+$\\\\)\"	\
visualize leading and/or trailing TABs.
   \" \\\\(\\t+\\\\) \"	visualize only TABs between SPACEs.

NOTE: Always enclose the elements to highlight in \\\\(...\\\\).
      Use exactly one pair of enclosing \\\\( and \\\\).

This variable is used when `whitespace-style' includes `tabs'."
  :type '(regexp :tag "TAB Chars"))