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    <p>As mentioned in other answers, <code>tie</code> applies to containers, and not to values, so there is no way to assign a tied variable to another variable and retain the tied properties.</p> <p>Since assignment is out, you need to pass the container into the <code>GetThing</code> routine. You can do this by reference as follows:</p> <pre><code>use strict; use warnings; main(); sub GetThing{ tie ${$_[1]}, 'mything', $_[0]; } sub main { my %m; GetThing('Fred' =&gt; \$m{pre}); print "1\n"; print $m{pre}; print "2\n"; print $m{pre}; print "3\n"; } package mything; require Tie::Scalar; my @ISA = qw(Tie::StdScalar); sub TIESCALAR { my $class = shift; bless { name =&gt; shift || 'noname', }, $class; } sub FETCH { my $self = shift; print "ACCESS ALERT!\n"; return " NAME: '$self-&gt;{name}'\n"; } </code></pre> <p>which produces the correct output.</p> <p>However, if you want to retain the assignment, you will need to use overloading, which applies to values (actually to objects, but they themselves are values). Without more detail on your intended purpose it is hard to give a complete answer, but this will meet your stated requirements:</p> <pre><code>use strict; use warnings; main(); sub GetThing{ return mything-&gt;new( shift ); } sub main { my %m; $m{pre} = GetThing('Fred'); print "1\n"; print $m{pre}; print "2\n"; print $m{pre}; print "3\n"; } package mything; sub new { my $class = shift; bless { name =&gt; shift || 'noname', }, $class; } use overload '""' =&gt; sub { # '""' means to overload stringification my $self = shift; print "ACCESS ALERT!\n"; return " NAME: '$self-&gt;{name}'\n"; }; </code></pre> <p>Both ties and overloads can get complicated, so read through all of the documentation if anything is not clear.</p>
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    1. COthat looks like it might do the trick. The purpose is to compute my strings on-demand, in a lazy fashion, and to also do some expensive operations on values as-needed. Our users may create many values, but end up only using a few. The users are non-expert to say the least, so if we can make it look like a plan string, thats best. I'll try it out and get back to you in a minute.
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    2. COworks like a charm! I've tweaked the title to better reflect my problem. I'd remove the first half of your answer.
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    3. CO@bukzor => you can also take a look at my module `List::Gen` on CPAN which contains a fairly robust implementation of lazy lista
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