Check out Tie::Toggle: 
use Tie::Toggle;

tie my $toggle, 'Tie::Toggle';
my @color = qw(black white);

print "$color[$toggle]\n" for 1..10;

[download]
Using more than one color? Tie::Cycle 
use Tie::Cycle;

tie my $color, 'Tie::Cycle', [qw(red white blue)];
print "$color\n" for 1..10;

[download]
Combine that with Color::Spectrum: 
use Tie::Cycle;
use Color::Spectrum qw(generate);

tie my $color, 'Tie::Cycle', [generate(4,'#ff00ff','#00ff00')];
print "$color\n" for 1..10;

[download]

jeffa

L-LL-L--L-LL-L--L-LL-L--
-R--R-RR-R--R-RR-R--R-RR
B--B--B--B--B--B--B--B--
H---H---H---H---H---H---
(the triplet paradiddle with high-hat)

In reply to (jeffa) 4Re: Anyone use "xor" in conditionals? by jeffa
in thread Anyone use "xor" in conditionals? by bsb

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