my $a = "foo";
  my $b = "bar";
  my $c = ".*";

  print "eq" if ($a eq $a);	# prints "eq"
  print "ne" if ($a ne $b);	# prints "ne"
  print "ne" if ($a ne $a);	# prints nothing
  print "RE" if $a =~ /$c/;	# prints "RE"
  print "RE" if $a =~ /f.*/;    # prints "RE"