Build your script library

You know, we are often in the position of having to perform tedious tasks repeatedly, yet fearing that by trying to automate we will lose more time, we… do the boring stuff.

In Unix and Linux System Administration Handbook, the authors suggest that sysadmins do not fall into the trap of believing that automation is only for big projects and that it requires elaborate planning.

Thinking of that section of the book, today, after not being able to sleep as well as I’d like the previous day, I gave this a shot. To my surprise, not only did it work, but it was also (if I remember correctly) way more efficient, than if I had done that by hand.

The script is as simple as it gets, I just needed to replace a property that was wrongly set in my notes. The fact that it is less than 10 lines, is a consequence of the library of small scripts and functions, which even though they may not be beautifully written, have tremendous practical value.

(cl-loop for file in (chatziiola/get-lecture-file-list "CCNA") do
         (message "Starting %s" file)
         (with-current-buffer (get-file-buffer file)
           (message "Inside the file")
           (goto-char (point-min))
           (if (search-forward "A.U.Th" nil t)
            (replace-match "CISCO")
            (message "Un-Successful search"))
           )
         )

In fact, with just a slight modification, this can turn into a function, allowing me to use it in the future without losing time re-implementing it, effectively solving the same problem again.

(defun chatziiola/correct-lecturefiles-course-property course
  "Fix the lectures' in COURSE, course property.

Get the property from the main (INFO) file of COURSE or, if that
is not set, replace current value with the default one"
  (cl-loop for file in (chatziiola/get-lecture-file-list course) do
           (with-current-buffer (get-file-buffer file)
             (goto-char (point-min))
             ;; Actually this part needs to be modified to be used in a more
             ;; generic environment, but for me this search is enough in 9 out
             ;; of 10 times, and that is why i dont mess with a modification in
             ;; the form of '#+course: .*\n'
             (if (search-forward "A.U.Th" nil t)
                 ;; See how a small function from another time may go a long way? ;P
                 (replace-match (chatziiola/get-lecture-institution course))
               (message "Un-Successful search in file: %s" file)))
           )
  )

I have to make a couple of points here:

1. You do not always save time by writing a script. You have to pick your battles. If writing the script is sure to take some time and will not be used often, making it hard to get your time back, it probably is a good idea to deal with it manually. No one wants that but sigh time is limited
2. You can always win something by writing a script. That something most of the times is experience, which you will take advantage of when found in similar situations. (This is more or less what I tell myself when a script took more time than I had anticipated :P)
3. Use the right tool for the job - utilize existing infrastructure. Once again, the script above is rather simple, and I had opened a python file to write it in, when I realized that writing it in elisp would most probably be a little bit better for me, since I have some functions I could use. That decision saved me some time. Imagine how much time one could save with an equivalent decision in a much more complicated script.
4. Organize your scripts properly. If they are not small functions that can be grouped together, consider bundling them all by topic or by programming language and creating a catalog, with a small description for each one. Ironically this, usually, is the kind of job that we tried to avoid in the first place, but in the long run it is definitely worth it.

Summing up, the thing is, that Rome was not built in a day. From my experience, one needs to start building their script arsenal, keeping track of the problems they have solved and in time, they will find that being able to utilize previous work saves them much time.