Here's my stab at it. By storing the original text in a function instead of a scalar I can delay interpolation of the $vars until call time. See this example: 
$text = sub {
<<EOT;
Dear $person,
I know that this text is $adjective.
But I wish it could be...
EOT
};

local $person    = 'Mom';
local $adjective = 'not interpolated';

print &$text;

[download]
I don't think this is quite what you were looking for, but I think it is along the right path. I have a feeling that something with eval might do the trick too, but I can't figure out how to get that to work right now.

In reply to Re: Dreaming of Post Interpolation by lhoward
in thread Dreaming of Post Interpolation by BBQ

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