<project xmlns:if="ant:if">

 <macrodef name="foobar">
  <attribute name="foo"/>
  <attribute name="verbose"/>
  <sequential>
   <echo>@{foo}</echo>
   <echoproperties prefix="ant" if:true="@{verbose}"/>
  </sequential>
 </macrodef>

 <!-- use foobar macrodef with different parameters (attribute values) -->
 <foobar verbose="yes" foo="1. yada,yada"/>
 <foobar verbose="no" foo="2. blabla.."/>

</project>

[echo] 1. yada,yada
[echoproperties] #Ant properties
[echoproperties] #Thu Sep 18 09:31:05 CEST 2014
[echoproperties] ant.core.lib=C:\ant194\lib\ant.jar
[echoproperties] ant.file=C:\area51\ant\tryme.xml
[echoproperties] ant.home=C:\ant194
[echoproperties] ant.java.version=1.7
[echoproperties] ant.library.dir=C:\ant194\lib
[echoproperties] ant.version=Apache Ant(TM) version 1.9.4 compiled on April 29 2014
[echo] 2. blabla..