The Chronicle

of a ColdFusion Expatriate

Creating Org Mode Structure Templates

November 23, 2016

Hopefully you already know that you can insert common markup blocks in Org Mode by entering a prefix like <s and pressing <M-TAB>. Org Mode publicly calls these “Easy Templates” but internally calls them “structure templates.” I wanted to be able to insert a couple of other common Org-specific blocks, so I figured out how to add my own.

Org Mode supports a few “blocks,” which you can read about beginning on the Blocks page of the Org documentation.

For example, if you want to insert a block of Emacs Lisp code into an Org document, you would write a block that looks like this:

#+BEGIN_SRC emacs-lisp
(defun org-xor (a b)
    "Exclusive or."
    (if a (not b) b))
#+END_SRC

It can be hard to remember, and tedious to type, the #+BEGIN_SRC bit, so Org includes this expansion capability that it refers to in its documentation as Easy Templates, but that is referred to in its source code as “structure templates.”

Getting straight to the point, I use the export features of Org Mode quite often, especially export to HTML (mostly for pasting into other formatted mediums such as email) and LaTeX/Beamer (for quick one-off slide decks). I usually write content directly into my “notes” file and then export a single subtree.

Exporting a subtree is very easy, simply trigger export with C-c C-e, toggle “export subtree” on with C-s, and press the appropriate export format buttons, like h o for “export as HTML and open in the default browser.”

If you’re a pro like me, you have set org-export-initial-scope to subtree so that you can skip the second step.

Let’s take HTML as an example. The default export settings when you export to HTML are crude at best. For one thing, the title of the document will be the subtree’s title, which is not always what you want. Worse, the filename of the HTML file will be the filename of the entire file the subtree is in. So essentially I wound up with a notes.org.html over and over.

You can fix that by adding some export options, and for subtree exports you put those into a property drawer. For me, that looks like this:

* Test Subtree Export
  :PROPERTIES:
  :EXPORT_FILE_NAME: actually-use-this-filename
  :EXPORT_TITLE: My Fascinating HTML Export
  :EXPORT_OPTIONS: toc:nil html-postamble:nil num:nil
  :END:

In this workflow there are two things that are annoying:

  1. I hate typing out :PROPERTIES:, and I use property drawers a lot. There is an Org function for this (org-insert-property-drawer), but I’m running out of good key bindings so I didn’t want to make another one for this.

  2. I’m not going to be able to memorize the precise format of all of my HTML export settings, let alone toc:nil html-postamble:nil num:nil.

This is where a structure template comes in handy.

The Goal

The goal is to be able to type something like <p and press <TAB> to insert the property drawer, and then something like <eh (for export html) and press <TAB> to insert my default HTML export options.

Structure templates are inserted as part of the org-cycle function, and so I have bound org-cycle to <TAB> in my config. If <TAB> doesn’t work for you, but <M-TAB> does, this is probably why.

On the Easy Templates manual page, it says:

You can install additional templates by customizing the variable org-structure-template-alist. See the docstring of the variable for additional details.

So this should be easy, we just need to add a new value to this list.

Create a New Template

The format of org-structure-template-alist is like this (abridged):

(("s" "#+BEGIN_SRC ?\n\n#+END_SRC" "<src lang=\"?\">\n\n</src>")
 ("e" "#+BEGIN_EXAMPLE\n?\n#+END_EXAMPLE" "<example>\n?\n</example>")
 ("q" "#+BEGIN_QUOTE\n?\n#+END_QUOTE" "<quote>\n?\n</quote>")
 ...)

This is an association list so each element of the outer list is a list with at least two elements. The first element is the letter to follow < in your template expansion trigger. The second element is the template itself, with a ? where the cursor should wind up at the end.

Most of the defaults have a third value, which is an “Emacs Muse”-style template. Muse is some kind of authoring system for Emacs that I know nothing about and don’t care about. You don’t need a third element for this to work, so just ignore it.

Cool, so we just add a new element to this list defining our template. Let’s do the :PROPERTIES: one:

(add-to-list 'org-structure-template-alist
             (list "p" (concat ":PROPERTIES:\n"
                               "?\n"
                               ":END:")))
Note that I am using the list function rather than a quoted list because I need Emacs to evaluate the return value of the concat function within the list. I am only using concat here to make the code more legible because the template string is multiple lines long. I like pretty code.

You can evaluate this expression by placing your cursor outside of the last closing parenthesis and calling eval-last-sexp (which I have bound to C-RET for just such an occasion).

Once you have evaluated that expression, the template should work right away! Open an Org file, enter <p on its own line, and hit <M-TAB> (or <TAB> if you bound org-cycle to it as I have).

But Longer Shortcuts Though?

If you read the source code of the function org-try-structure-completion, you will notice that the regular expression will match one or more letters, so even though Org only ships with one-letter expansion triggers, you can create longer ones if you want to.

Here is my HTML export options template:

(add-to-list 'org-structure-template-alist
             (list "eh" (concat ":EXPORT_FILE_NAME: ?\n"
                                ":EXPORT_TITLE:\n"
                                ":EXPORT_OPTIONS: toc:nil html-postamble:nil num:nil")))

Now I can do <p<TAB> and then immediately <eh<TAB> and I’m all ready to add a filename and a title and export this subtree to HTML!

Have any bright ideas for new Org Mode structure templates? Leave them in the comments below!

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