I’d try reversing the string, split it, then reverse all the pieces. That way you can use a variable-width look-ahead assertion instead of a(n unsupported) variable width look-behind assertion. 
$_ = "#@##@###@####@#####@";
$_ = reverse;
my @pieces = reverse (split /\@(?=(?:##)*(?!#))/);                    
+          
for (@pieces) {
    $_ = reverse;
}
print "@pieces\n";

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The regex is a little hairy; it has a negative look-ahead assertion inside the positive look-ahead assertion.

In reply to Re: Splitting on escapable delimiter by Anonymous Monk
in thread Splitting on escapable delimiter by Daryn

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