<PrincessBride>I do not think that means what you think it means.</PrincessBride> You can't use a string as an index to an array... Perhaps you meant

#!/usr/bin/perl
@all = ($love{'fair'}, $war{'fair'});
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Though I think that warps the semantics of the original poem. Linguistically, it parses differently (paraphrased, it's "All is that which is fair in love and that which is fair in war"). Me, I'd write

#!/usr/bin/perl
$love{'all'}='fair';
$war {'all'}='fair';
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Or perhaps:

#!/usr/bin/perl
$love{'all'}='fair';
&war;

sub war {
    print "All is fair in love and war.";
}
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