Take the 2-minute tour ×  How to check if property ${foo} has
been set?  Bonus question: how to escape $ sign in <echo> so I
could output ${foo} string (not the foo variable substitution)?
PS: tried to google and read documentation, but couldn't find
the answers. It's likely I'm missing something  share|improve
this question add comment  1 Answer  up vote 8 down vote
accepted  You need to place an isset element inside the if
element.      <isset property="foo" />  The manual is available
here.  share|improve this answer add comment  Your Answer