clm.el

;; If the file exists, execute the block.
;;
;;
;; My SEKRET SETTINGS OMG
;;(ext*with-file-exists-f "~/Dropbox/.github.config.el"
;;			(load "~/Dropbox/.github.config.el"))
;;
(defmacro ext-with-file-exists (file block)
  "Execute the form if the file exists."
  `(and (file-exists-p ,file)
        (progn ,block)))


;;
;; Same as above, but with an argument passed to
;; the block that is the name of the file in question.
;;
;; My SEKRET SETTINGS OMG
;;(ext*with-file-exists-f "~/Dropbox/.github.config.el"
;;			(load the-file))
;;
(defmacro ext-with-file-exists-f (file &rest block)
  "Like with-file-exists, except that it makes a (let) variable available called 'the-file' with the name of the checked file."
  `(let ((the-file ,file))
     (and (file-exists-p ,file)
          (funcall (lambda ()
                     ,@block)))))



;;
;;
;; HEY! Hey, you!
;; Do you need to do some really stupid shit?
;; Well, then you should wrap it in this!
;;
;;
;; http://curiousprogrammer.wordpress.com/2009/06/08/error-handling-in-emacs-lisp/
;;

(defmacro ext-safe-wrap (fn &rest clean-up)
  `(unwind-protect
       (let (retval)
         (condition-case ex
             (setq retval (progn ,fn))
           ('error
            (message (format "Caught exception: [%s]" ex))
            (setq retval (cons 'exception (list ex)))))
         retval)
     ,@clean-up))


;;
;; package.el helpers...
;;

(unless (featurep 'package)
  (progn
    (require 'package)
    (package-initialize)))


;;
;; If pkg is installed already, don't do anything.
;; Otherwise, install it.
;;
(defun ext-package-ensure (pkg)
  (or (progn
        (ignore-errors (require pkg))
        (ext-package-get-version-for-name pkg))
      (ignore-errors
        (and (package-install pkg)
             (message (symbol-name pkg))))))

(defun ext-package-delete (pkg)
  (let ((v (ext-package-get-version-for-name pkg)))
    (and v (package-delete pkg v))))



(defun ext-package-get-version-for-name (pkg)
  (let ((lx (assq pkg package-alist)))
    (and lx
         (package-version-join
          (package-desc-vers (cdr lx))))))


;;
;;
;; Maybe in addition I should
;; do an (or (featurep ..)
;;           (boundp package-alist)
;; instead of (and (featurep ..)
;;
;;
(defmacro ext-with-has-package-el (block)
  `(and (featurep 'package)
        ,block))


(defun ext-package-what-packages ()
  (mapcar (lambda (x)
            (symbol-name (car x))) package-alist))


(provide 'clm)