The UI language
The element ui:ifexpr
The element expects in the expr attribute a number which is interpreted as boolean value. If the number is non-zero, the inner nodes of the element are expanded and the condition code is set to true; otherwise the inner nodes are ignored, and the conditon code is set to false.
Level: Control structure
<!ELEMENT ui:ifexpr ANY> <!ATTLIST ui:ifexpr expr CDATA #REQUIRED >
All page body elements may occur as sub elements.
Note that template parameters and bracket expressions within ui:if are unconditionally evaluated. See ui:cond for a discussion of the consequences of this fact.
<ui:ifexpr expr="$[int-gt(n,1)]"> The result has more than one solution: ... </ui:ifexpr>