bug#15201: 24.2; extensions/enhancements to package.el

bug#15201: 24.2; extensions/enhancements to package.el

[Ryan Davis]

I know that using cl is frowned upon... but I'm writing this code to be
compatible with 24.2 so I can't rely on cl-lib (since this is an
extension to the system used to install cl-lib). I'm only using it for
set-difference and am open to modifications to make it more
portable/acceptable. You can see this code in:

https://github.com/zenspider/package/blob/master/package%2B.el#L70-L104

  (require 'cl)

  (defun package-version-for (name)
    "Returns the installed version for a package with a given NAME."
    (package-desc-vers (cdr (assoc name package-alist))))

  (defun package-delete-by-name (name)
    "Deletes a package by NAME"
    (message "Removing %s" name)
    (package-delete (symbol-name name)
                    (package-version-join (package-version-for name))))

  (defun package-maybe-install (name)
    "Installs a package by NAME, but only if it isn't already installed."
    (unless (package-installed-p name)
      (message "Installing %s" name)
      (package-install name)))

  (defun package-deps-for (pkg)
    "Returns the dependency list for PKG or nil if none or the PKG doesn't exist."
    (let ((v (cdr (assoc pkg package-alist))))
      (and v (package-desc-reqs v))))

  (defun package-transitive-closure (pkgs)
    (let ((deps '()))
      (dolist (pkg pkgs deps)
        (add-to-list 'deps pkg)
        (dolist (new-pkg (mapcar 'car (package-deps-for pkg)))
          (add-to-list 'deps new-pkg)))))

  (defun package-cleanup (packages)
    "Delete installed packages not explicitly declared in PACKAGES."
    (let ((removes (set-difference (mapcar 'car package-alist)
                                   (package-transitive-closure packages))))
      (mapc 'package-delete-by-name removes)))

;;; finis

In GNU Emacs 24.2.1 (x86_64-apple-darwin12.2.0, NS apple-appkit-1187.34)
of 2012-09-20 on greed.local
Windowing system distributor `Apple', version 10.3.1187
Configured using:
`configure '--prefix=/usr/local/Cellar/emacs/24.2' '--without-dbus'
'--enable-locallisppath=/usr/local/share/emacs/site-lisp'
'--infodir=/usr/local/Cellar/emacs/24.2/share/info/emacs' '--with-ns'
'--disable-ns-self-contained''

Important settings:
  value of $LC_ALL: nil
  value of $LC_COLLATE: nil
  value of $LC_CTYPE: nil
  value of $LC_MESSAGES: nil
  value of $LC_MONETARY: nil
  value of $LC_NUMERIC: nil
  value of $LC_TIME: nil
  value of $LANG: nil
  value of $XMODIFIERS: nil
  locale-coding-system: nil
  default enable-multibyte-characters: t

Major mode: Fundamental

Minor modes in effect:
  tooltip-mode: t
  mouse-wheel-mode: t
  tool-bar-mode: t
  menu-bar-mode: t
  file-name-shadow-mode: t
  global-font-lock-mode: t
  blink-cursor-mode: t
  auto-composition-mode: t
  auto-encryption-mode: t
  auto-compression-mode: t
  line-number-mode: t
  transient-mark-mode: t

Recent input:
s-x <escape> x r e p <tab> o <tab> r <tab> <return
>

Recent messages:
For information about GNU Emacs and the GNU system, type C-h C-a.
kill-region: The mark is not set now, so there is no region
Quit
Making completion list... [2 times]

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Features:
(shadow sort gnus-util mail-extr emacsbug message format-spec rfc822 mml
mml-sec mm-decode mm-bodies mm-encode mail-parse rfc2231 mailabbrev
gmm-utils mailheader sendmail regexp-opt rfc2047 rfc2045 ietf-drums
mm-util mail-prsvr mail-utils help-mode easymenu view time-date tooltip
ediff-hook vc-hooks lisp-float-type mwheel ns-win tool-bar dnd fontset
image fringe lisp-mode register page menu-bar rfn-eshadow timer select
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georgian utf-8-lang misc-lang vietnamese tibetan thai tai-viet lao
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hashtable-print-readable backquote make-network-process ns multi-tty
emacs)

bug#15201: 24.2; extensions/enhancements to package.el

[Stefan Monnier]

> I know that using cl is frowned upon... but I'm writing this code to be
> compatible with 24.2 so I can't rely on cl-lib (since this is an
> extension to the system used to install cl-lib). I'm only using it for
> set-difference and am open to modifications to make it more
> portable/acceptable. You can see this code in:

Use of CL is generally discouraged, and is not allowed at run-time for
packages included in Emacs.  IOW As long as your code is not meant to be
included in Emacs you don't need to worry too much about it.

OTOH, the code you sent doesn't work with the package.el that's in
Emacs's current trunk (e.g. package-delete now only takes a single argument).

One more thing: I like the idea of having a declarative list of
"packages that should be installed" so as to be able to delete packages
that were installed as dependencies but aren't needed any more.  So I'd
welcome patches that add such functionality to package.el.


        Stefan

bug#15201: 24.2; extensions/enhancements to package.el

[Lars Ingebrigtsen]

(I'm going through old bug reports that unfortunately weren't resolved
at the time.)

It seems like the conclusion here was that the proposed helper functions
didn't seem very vital to add, so I'm closing this bug report.

-- 
(domestic pets only, the antidote for overdose, milk.)
   bloggy blog: http://lars.ingebrigtsen.no