;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;                 Autocomplete
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
(defadvice cperl-indent-command
  (around cperl-indent-or-complete)
  "Changes \\[cperl-indent-command] so it autocompletes when at the en
+d of a word."
  (if (looking-at "\\>")
      (dabbrev-expand nil)
    ad-do-it))
(defun cperl-dabbrev-installer ()
  (set (make-local-variable 'dabbrev-case-fold-search) nil)
  (set (make-local-variable 'dabbrev-case-replace) nil))
(eval-after-load "cperl-mode"
  '(progn
     (require 'dabbrev)
     (ad-activate 'cperl-indent-command)
     (add-hook 'cperl-mode-hook #'cperl-dabbrev-installer)))
[download]

Okay. The Eclipse fanboys will say that doesn't complete methods and such since it's just textual, but dabbrev works well in practice, and is a wonderful thing for all kinds of documents. btw, one nice trick I use for indent-or-complete commands is to complete on the second "TAB" when the line hasn't moved, rather than when at end-of-word, like so (pseudocode):

(defun my-indent-or-complete ()
  (interactive)
  (let ((pos (point)))
    (indent-command)
    (when (and (= pos (point))
           (eq last-command 'my-indent-or-complete))
      (complete-command))))
[download]

See also Hack #5 Autocomplete Perl Identifiers in Vim in Perl Hacks - Tips & Tools For Programming, Debugging, and Surviving by chromatic with Damian Conway and Curtis "Ovid" Poe. That has a nice script for trolling your @INC to make a file of autocompletion candidates. That could be hacked into dabbrev so you'd get better candidates than just "whatever is near or recent."

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