Modifying DIRECTORY

[Eyvind Ness <eyvind.ness@hrp.no>]

  ;; Date: Wed, 21 April 93, 16:05 CDT
  ;; From: berger@cs.uchicago.edu
  ;;
  ;; The Allegro (4.1) CL version of the function DIRECTORY returns its
  ;; list of pathnames in modification-date order (ala ls -c). I'm using
  ;; code written elsewhere which uses this function, but assumes the
  ;; pathnames are in alphabetical order. The Allegro Manual warns against
  ;; messing with the package-lock system, but can anyone tell me what sort
  ;; of disaster I might be courting by doing the following?
  ;; 
  ;; 
  ;; (let ((oldirectory (symbol-function 'directory)))
  ;;   (excl:without-package-locks
  ;;    (defun DIRECTORY (&rest args)
  ;;      (sort
  ;;       (apply oldirectory args)
  ;;       #'string-lessp
  ;;       :key #'file-namestring))
  ;;    )
  ;;   )

Hi Jeff,

I'm also a bit annoyed by the persistence with which Allegro protects
the built-in CL symbols - I can't even locally override CL fundefs
within an FLET/LABELS without having a flood of warnings thrown at me.

In your case, however, you might want to consider the ADVICE util to
modify the DIRECTORY function:

   USER(11): (directory ".")
   (#p"./errno.o" #p"./top-level-wrapper.fasl" #p"./top-level-wrapper.lisp.~1~"
    #p"./TAGLIST.~31~" #p"./TAGS.~31~" #p"./TAGLIST.~32~" #p"./COPMA-II.lisp"
    #p"./top-level-wrapper.lisp" #p"./TAGS.~32~" #p"./TAGLIST" ...)

Unsorted, default listing returned.

   USER(12): (excl:defadvice directory :around
	      (sort :do-it #'string-lessp :key #'file-namestring))
   DIRECTORY

   USER(13): (directory ".")
   (#p"./bup-4-4-92" #p"./COPMA-II.lisp" #p"./enlib" #p"./errno.o" #p"./example" #p"./junk"
    #p"./kernel" #p"./Makefile" #p"./manual-make" #p"./networking" ...)
   USER(14): 

Sorted, as intended.

Cheers,
Eyvind.


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