title: variable bound check in a clips rule RHS
body: <pre><code>checkIntfIntVlanMemberConfigRule = """
      (defrule checkSubIntfIntVlanMemberConfigRule
      (checkIntf (intf ?intf) )
      (SwitchIntfConfig (intf ?intf) (switchportMode "routed") (nativeVlan          ?intVlan))
      (or (not (VlanStatus (vlan ?intVlan) (intf ?intf)) )
       ?f &lt;- (VlanStatus (vlan ?intVlan) (intf ?intf)) )
      =&gt;
      (if (isbound ?f) then (printout t "PASS: vlanStatus exists for " ?intf " " ?intVlan crlf) (return 0) )
      (printout t "vlanStatus does not exist for " ?intf " " ?intVlan crlf)
      )"""
  </code></pre>
  
  <p>In the above clips rule, what is the equivalent clips buildin function for (isbound ?f) ? In general is there any buildin function to check in RHS if a variable was bound in LHS?</p>