Auto install emacs packages with MELPA

Question

I want to declare all packages that I want to use in emacs in a init.el file. I wonder if its possible to load the missing packages with e.g. MELPA when I startup e

Answer 1

A bit of code in your init file can do that quite easily:

(setq my-onlinep nil)
(unless
    (condition-case nil
        (delete-process
         (make-network-process
          :name "my-check-internet"
          :host "elpa.gnu.org"
          :service 80))
      (error t))
  (setq my-onlinep t))

(setq my-packages
      '(ack-and-a-half
        ac-nrepl
        ... more packages here ...
        web-mode
        yaml-mode
        yari
        yasnippet))

(when my-onlinep
  (package-refresh-contents)
  (cl-loop for p in my-packages
           unless (package-installed-p p)
           do (package-install p)))

The online check is not really needed but helps to avoid getting a stuck Emacs startup when there is no internet connection.

For my full config see here: http://steckerhalter.co.vu/steckemacs.html#sec-2-5