Try/try.el
2014-11-13 23:20:08 +01:00

55 lines
1.8 KiB
EmacsLisp

;;; -*- lexical-binding: t -*-
(require 'package)
(require 'url)
(defvar try-tmp-dir "/tmp/")
(defun try-newest-package-installed-p (package)
"Return true if the newest available PACKAGE is installed."
(when (package-installed-p package)
(let* ((local-pkg-desc (or (assq package package-alist)
(assq package package--builtins)))
(newest-pkg-desc (assq package package-archive-contents)))
(and local-pkg-desc newest-pkg-desc
(version-list-= (package-desc-vers (cdr local-pkg-desc))
(package-desc-vers (cdr newest-pkg-desc)))))))
(defun try-raw-link-p (url)
(string-match-p "[^:]*://\\([^?\r\n]+\\).*\.el?$" url))
(defun try-raw-link (url)
(with-current-buffer (url-retrieve-synchronously url)
(condition-case nil
(progn
(eval-region (search-forward-regexp "^$") (point-max))
(message "Trying!"))
((debug error)
(message "Could not parse %s" url) nil))))
(defun try-compose (f g)
(lambda (&rest x) (funcall f (apply g x))))
(defun try-package (package)
(unless package--initialized
(package-initialize t))
(unless package-archive-contents
(package-refresh-contents))
(if (try-newest-package-installed-p package)
(message "Already installed.")
(message "Trying %s!" (symbol-name package))
t))
(defun try ()
"Takes an URL to a .el-file, and evaluates it."
(interactive)
(let ((url-or-package (completing-read
"url or package: "
(mapcar (try-compose 'symbol-name 'car)
package-archive-contents))))
(cond ((try-raw-link-p url-or-package) (try-raw-link url-or-package))
((try-package (intern url-or-package)))
(t (message "Couldn't find a sensible way to try this.")))))
(provide 'try)