You simply have a hash where each element in the set represents a key and its corresponding value is 1 or some other true value. 
   my (%fruits,%vegetables);
   $fruit{apple}=1;
   $fruit{orange}=1;
   $fruit{banana}=1;
   $vegetable{corn}=1;
   $vegetable{carrot}=1;
   
   #test whether apple is in the set fruit
   if($fruit{apple}){  #test for inclusion in a set
      print "apple is a fruit";
   }

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In reply to Re: How do I use a hash as a set? by vroom
in thread How do I use a hash as a set? by vroom

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