Ticket #4421: testVarInPrefs.xml

<config>
   <ask var="x" input="true" text="Please enter angle"/>
   <messagebox text="You entered x=${{x}}"/>

   <if test="" notequals="${{x}}"> 
   <messagebox text="set angle snapping to x and 45 degrees only"/>
   <preferences operation="replace">
        <list key="draw.anglesnap.angles">
            <entry value='${{x}}'/>
            <entry value='45'/>
        </list>
   </preferences>
   </if>
</config>