Variable: regexp-unmatchable

regexp-unmatchable is a variable defined in subr.el.gz.

Value

"\\`a\\`"

Documentation

Standard regexp guaranteed not to match any string at all.

View in manual

Probably introduced at or before Emacs version 27.1.

Source Code

;; Defined in /usr/src/emacs/lisp/subr.el.gz
;; The initial anchoring is for better performance in searching matches.
(defconst regexp-unmatchable "\\`a\\`"
  "Standard regexp guaranteed not to match any string at all.")