Here we show how to add a rule to the Tiddler Icon Cascade that causes tiddlers with the tag TableOfContents to be given the "globe" icon and tiddlers with the tag Working with TiddlyWiki to be given the "help" icon .

First, we add a new step to the tiddler icon cascade. The new filter step is:

[tag[TableOfContents]then[$:/core/images/globe]]
[tag[Working with TiddlyWiki]then[$:/core/images/help]] 

It can be read as:

If the tiddler has the tag "TableOfContents" then return $:/core/images/globe
Else if the tiddler has the tag "Working with TiddlyWiki" then return $:/core/images/help

The tiddler icon cascade is defined by the tag $:/tags/TiddlerIconFilter, so we need to create a configuration tiddler with that tag.

We also need to make sure that it is inserted at the correct point in the cascade:

• The new rule must be after the "icon-field" rule to ensure that tiddlers with an explicit icon field will respect the value of that field
• The new rule must be before the "default" icon otherwise it will never be seen if the default icon is specified

The control panel "Cascades" tab shows that this can be achieved by inserting the new step immediately before the default step using the list-before field.

The full list of fields in the configuration tiddler is: