Skriftlig Info ➜ DITA publishing ➜ DITA variables ➜ Variable definitions using topic maps

In the procedures, descriptions and examples I use the <keyword> element. In many DITA systems, you can also use other elements. The elements must be defined in the system files that control the publishing system's functionality. Check with your system supplier for more information about this.

I recommend that you standardize the use of the <keyword> element for variables. Although it is permitted to use other elements, it is easier to be consistent. This consistency increases understanding in the team and facilitates maintenance. Especially for new users, it will be easier to identify which elements are variables and which are not.

A standard topic map is used.

This is the required code to define a variable called "VARIABLE" with a value set to "VALUE". The code will not look like this in your editor, since most editors prefer a more user friendly presentation.

<map>
...
<keydef keys="VARIABLE">
  <topicmeta>
    <navtitle>
      <keywords>
        <keyword>VALUE</keyword>
      </keywords>
    </navtitle>
  </topicmeta>
</keydef>
...
</map>

You can create as many <keydef> definitions as you want in the topic map, and each can have any value you want.

If any of the values have normal text that needs translation, the topic map must be included in the files you send to the translator. If you need to do this I recommend that you document each and every variable and explain how they are used.

The variable "VARIABLE" can be used in a topic or library topic as follows:

<p>
...
<keyword keyref="VARIABLE">
...
</p>

The <keyword> tag can be placed anywhere it is needed. In this example, I've used it in a <p> element, but you could just as easily place it in, say, a <title> or <cmd> element. Use the keyref attribute to retrieve the correct variable.

When you use the <keyword> tag in a topic or topic library, the content of VALUE can be any random text. You can also type whatever you want in the <keyword> tag. When the document is published, the publishing process will automatically retrieve and insert the correct value from the definition. This automatic process means you can insert the <keyword> tag from any topic library or copy it from another topic. Just make sure the keyref attribute points to the correct variable.

The map with the <keydef> definitions must be inserted into the <frontmatter> tag in your bookmap. Use the <mapref> tag.