my $seen = 0;
	while (<$fh>)
	{
		if ( !$seen and m/^alpha$/)
		{
			$seen = 'yes indeed';
			print "true\n";
		}else{
			print "false\n";
		}
	}


##</code><code>##

foo
bar
alpha
beta
gamma
delta


##</code><code>##

Original:
false
false
true
false
false
false

Flipflop:
Argument "" isn't numeric in numeric gt (>) at test.pl line 21, <$fh> line 1.
false
Argument "" isn't numeric in numeric gt (>) at test.pl line 21, <$fh> line 2.
false
false
true
true
true

Flag:
false
false
true
false
false
false