Perl 5.6 already has them (although it's labeled "experimental"), and they do use the above syntax (minus the eval stuff, which is needed to define and compile sub code at run-time). More specifically:
sub mysub : lvalue { $myvar; }
Check out perlsub for a more thorough discussion.

In reply to Re: Re: lvalue subs of a run-time persuasion by MeowChow
in thread lvalue subs of a run-time persuasion by MeowChow

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