Backlink: §2020-05-13-1815 Customizing Zetteldeft

This note is on link IDs. For customization of links, see note §2020-05-15-0908.

Different Zettelkasten use different types of identifiers to refer to notes. Luhmann (§2020-02-07-2328) relied on an intricate naming scheme to string his physical notes together and to be able to refer to them. Digital Zettelkasten often use IDs generated based on time.

By default, Zetteldeft uses %Y-%m-%d-%H%M to generate IDs for new notes. This can be changed by customizing zetteldeft-id-format. Its value should be a string with placeholders accepted by the format-time-string function.

To detect these IDs as such, Zetteldeft uses a regular expression. This is stored in zetteldeft-id-regex. When you change the zetteldeft-id-format, you need to change this regex accordingly.

This regular expression is [0-9]{4}(-[0-9]{2,}){3}. This means that, by default, it looks for: a set of four digit, followed by three sets of hyphens and at least 2 digits each.

Note that the actual value of zetteldeft-id-regex as a string is [0-9]\\{4\\}\\(-[0-9]\\{2,\\}\\)\\{3\\}, as we need to use \\’s to escape the ( ) { } brackets.

Tip: use Emacs’ interactive re-builder to construct your regular expressions.