new ops

To play a bit with ASDF I've been writing a couple of operations that
I find fairly useful, so I thought about sharing them.

Enjoy,

-- 
walter pelissero
http://www.pelissero.de

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;;;  asdfadd.lisp --- addenda to asdf

;;; This file adds three operations to ASDF standard repertoire:
;;; pack-op, tag-op and stat-op.  The first one creates a tar/zip
;;; archive of the files in a system.  The second one creates a tag
;;; file (Emacs or Vi compatible).  The last one, stat-op, gives some
;;; statistics on the system files.  Check the documentation of each
;;; class for further details.
;;;
;;; Usage:
;;;   (asdf:oos 'asdf:pack-op :sysname &key (archive-type :tgz) (output-file nil))
;;;   (asdf:oos 'asdf:tag-op :sysname &key (tags-type :etags))
;;;   (asdf:oos 'asdf:stat-op :sysname &key (source-only nil))

(in-package :asdf)

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;;; A few bits lifted from CLOCC's port system, so that ASDF can stay
;;; independent.