Surely, that module isn't capable of reversing the concatenation of its arguments, and then performing it again, is it? Perhaps you meant something more like this: 
$a = '';
$str = "blabla" . postpone_forever( $a ) . "blabla";
$a = "XXX";
print "$str\n";

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In reply to Re^2: Create string with a delay by Anonymous Monk
in thread Create string with a delay by jeanluca

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