sub member
{
   my $item = shift;
   my @found = grep $_[$_] eq "$item", 0..$#_;
   if (defined @found)
   {
      return $found[0] + 1;
   }
   else
   {
      return 0;
   }
} ## end member()

@x=(0,1,3);
print member(2,@x),"\n"; # not in list 
print member(0,@x),"\n"; # 1st item in list
print member(2,@x),"\n"; # not in list, again