;;; Details of groups in this are used in `cperl-imenu--create-perl-index'
;;;  and `cperl-outline-level'.
;;;; Was: 2=sub|package; now 2=package-group, 5=package-name 8=sub-name (+3)
(defvar cperl-imenu--function-name-regexp-perl
  (concat
   "^\\("				; 1 = all
       "\\([ \t]*package"		; 2 = package-group
          "\\("				; 3 = package-name-group
	    cperl-white-and-comment-rex ; 4 = pre-package-name
	       "\\([a-zA-Z_0-9:']+\\)\\)?\\)" ; 5 = package-name
       "\\|"
          "[ \t]*sub"
	  (cperl-after-sub-regexp 'named nil) ; 8=name 11=proto 14=attr-start
	  cperl-maybe-white-and-comment-rex	; 15=pre-block
   "\\|"
     "=head\\([1-4]\\)[ \t]+"		; 16=level
     "\\([^\n]+\\)$"			; 17=text
   "\\)"))

(defvar cperl-outline-regexp
  (concat cperl-imenu--function-name-regexp-perl "\\|" "\\`"))

;; ...

;; Suggested by Mark A. Hershberger
(defun cperl-outline-level ()
  (looking-at outline-regexp)
  (cond ((not (match-beginning 1)) 0)	; beginning-of-file
;;;; 2=package-group, 5=package-name 8=sub-name 16=head-level
	((match-beginning 2) 0)		; package
	((match-beginning 8) 1)		; sub
	((match-beginning 16)
	 (- (char-after (match-beginning 16)) ?0)) ; headN ==> N
	(t 5)))				; should not happen