Hello nysus,

This is a frequent question as choroba said and was a question i made here sometime ago too; it happens when you try to understand how Perl works behind the courtains.

Anyway you must understand that you investigate such approach only for learning purpose, then in code you must use other tools like calling a subroutine or if the codebase is big, using templates Template::Toolkit

When i asked for Perl's wisdom at Interpolation: when it occurs? another beginner question.. i got indeed good replies and between them a genial one by tobyink that i propose here:

# tobyink's code http://www.perlmonks.org/?node_id=1020521
use v5.10;
use strict;
use warnings;

sub delayed (&) {
    package delayed;
    use overload q[""] => sub { $_[0]->() }, fallback => 1;
    bless shift;
}

my $string = delayed {"Look $::person, no $::thing!"};

$::person = "Ma";
$::thing  = "stringy eval";
[download]

tobyink was made so curoius by that question and he developped in one week his String::Interpolate::Delayed.
Be sure to read the docs for that module, specially the caveats part

HtH
L*