perldoc perlsub says of lvalue subs: 
They violate encapsulation. A normal mutator can check the supplied ar
+gument before setting the attribute it is protecting, an lvalue subro
+utine never gets that chance.

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A tied scalar can check before setting. Of course, in your example, if you had tied the foo element, then you'd have encapsulation.
We're not really tightening our belts, it just feels that way because we're getting fatter.

In reply to Re^2: Encapsulation without methods by Roy Johnson
in thread Encapsulation without methods by Roy Johnson

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