Still probably not what you are looking for (i.e. no refs), but closer maybe? (at least no regex) 
#!/usr/bin/perl -slw
use strict;

my $str = 'aaaaaaaaaa';

print recur($str);

sub recur
{
    my $s = shift;
    return "" if length($s)==0;
    substr($s,1,-1) = recur(substr($s,1,-1));
    return "($s)";
}

[download]

-- All code is 100% tested and functional unless otherwise noted.

In reply to Re^3: Scalar refs, aliasing, and recursion weirdness. by sleepingsquirrel
in thread Scalar refs, aliasing, and recursion weirdness. by BrowserUk

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