Lacking Natural Simplicity

I used to record the books that I read on this blog, but that took too much effort. However, if I don't record the books I read, I sometimes can't remember whether I read a particular book or not, especially with Kindle Unlimited books. (Was it the seventh book of the series that I read last, or the eighth?)

I record the books that I read in emacs using org-mode and — since today — org-capture. Here's what the org file looks like:

* 2022
** Read
*** : Title of Book I Haven't Finished Reading -- https://www.amazon.com/amazon-book-link-if-it-exists
...
*** 2022-05-21: Title of Book I **Have** Finished Reading -- https://www.amazon.com/amazon-book-link-if-it-exists
...
** Did not finish
*** : Title of Book I Won't Finish Reading -- https://www.amazon.com/amazon-book-link-if-it-exists
...
* 2021
* Previously read, sometime
** Title of Book I Finished Reading at some indeterminate date in the past -- https://www.amazon.com/amazon-book-link-if-it-exists
...

I keep the org file in a git repository hosted online so I can edit it on whatever computer is close at hand, or on my cell phone. (Having a git client with a simple editor on my phone is wonderful!)

When I start reading a book I create a new entry by selecting the title and author of the book on its Amazon page, use the Chrome extension Create Link to create a plain text link, which I then insert into the org file at the right heading level and with a :␢ (a colon followed by a blank space) after the asterisks of the heading and before the link. When I'm done with reading the book I put the ISO 8601 date (YYYY-MM-DD) before the colon.

I wrote a script today to count how many books I've read so far this year:

#! /usr/bin/env bash

YEAR=$(date '+%Y')
LAST_YEAR=$((YEAR - 1))

sed -E -n "/^\* $YEAR/,/^(\*\* Did not finish|\* $LAST_YEAR)/p" $READ_FILE |
    sed -e "/^* $YEAR/d" -e "/^** Read/d" \
        -e "/^(\*\* Did not finish|\* $LAST_YEAR)/d" |
    sed -E -n "/^\*\*\*[ \t]+[0-9]/p" |
    wc -l

This gets all the lines for this year, or just up to the ones that I did not finish, if there are any yet, then gets read of the leading

This works pretty well.

And so far I've read 227 books this year.

And then I got to thinking: I could probably use org-capture to automate finding the file, finding the right place to insert the information, and then copying the link from the clipboard and inserting it along with the heading formation!

Here's the org-capture-templates value I use for this:

(setq org-capture-templates
      `(("b" "Add book about to read" entry
         (file+olp ,(expand-file-name "~/Repos/tkb-org/Books/read.org")
                   ,(format-time-string "%Y") "Read")
         "*** : %c" :prepend t)))

You'll want to read Capture templates to understand how this works.

Of course, then I thought: what if my emacs session lasts from one year into the other, and I then add a new book? It will have the wrong year!

And then I immediately thought of Advising Emacs Lisp Functions! (I feel old — it was the defadvice function when I started using it.)

So I added the following code:

  (defvar tkb-org-year (format-time-string "%Y")
    "The year the current emacs session was started, for use with org-capture.")
  (defun tkb-org-capture-advice-update-year (&optional goto keys)
    "Update ‘tkb-org-year’ and update the entry for adding a book in
‘org-capture-templates’ to use the new value."
    (let ((new-year (format-time-string "%Y")))
      (unless (string-equal tkb-org-year new-year)
        (setf tkb-org-year new-year)
        (setf (--> "b" (assoc it org-capture-templates)
                   (assoc 'file+olp it) (nth 2 it))
              tkb-org-year))))
  (advice-add 'org-capture :before #'tkb-org-capture-advice-update-year)

I tested this by manually setting tkb-org-year to "2021" and capturing a new book. It worked fine!