I don't know why, but on a hunch, I tried this change:

#! perl -slw
use strict;

sub recurse {
    print ">> '${ $_[ 0 ] }'";
    if( length ${ $_[ 0 ] } ) {
       #recurse( \            substr( ${ $_[ 0 ] }, 1, -1 )   );  #old
        recurse( \( my $boo = substr( ${ $_[ 0 ] }, 1, -1 ) ) );  #new
        ${ $_[ 0 ] } = " ( ${ $_[ 0 ] } ) ";
    }
    print "<< '${ $_[ 0 ] }'";
    return;
}

my $str = 'aaaaaaaaaa';
recurse \$str;

print $str;

[download]

and it worked. I leave it up to you to explain it (cause I'm going home!)

I'm don't think this is the output you want, because it would be a very convoluted way of getting it. But you didn't specify what you wanted.

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

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