I get your point, but I appear to be missing it because I'm never returning an rvalue. In the sample usage I've listed, I'm not using any rvalues: it's always returning the *actual var*, OR a *tied var* -- both are lvalues, but in non-lvalue context, I can return the variable directly in the belief that it is not being modified or assigned to. 
$p->{_url}  # simply var access (no tied usge)

[download]

In the lvalue case I would need to return a more expensive case, like: 

$p->{_tied_url}

[download]
So I can do post-assignment-processing.

It's a matter of optimization/performance -- not function.

Are we on the same page yet?

In reply to Re^10: can sub check context for lvalue vs rvalue context? by perl-diddler
in thread can sub check context for lvalue vs rvalue context? by perl-diddler

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