Further conditional rendering rules can be written with the <if> syntax. It is possible to test multiple attribute values and to render prefix and suffix strings. These strings are nested within the text generated by <render-before> and <render-after>. <if> conditions may only occur beneath <self>, and any number of occurrences are allowed. Each <if> has exactly two children: an <attr-value> node and either a <prefix> or a <suffix> sub-action node. The content of <prefix> or <suffix> is the text to be rendered.
Example 1: This rule renders the contents of the <sic> tag in square brackets. If the exclam attribute has the value "yes", an exclamation mark is rendered before the right bracket.
<attr-value name="exclam" value="yes"/>