Unlang check if module exists before if else block

[Arnab Roy]

   Hello,

   Is it possible to check in unlang if module is enabled for e.g.
   something like this

   if(mschap) --> if mschap is enabled in mods-enabled/
   {
   .....
   }
   else{
   .........
   }

   Any pointers would be greatly appreciated.

   Many Thanks
   Arnab