The problem is the way how you use substr

substr can be used as lvalue

Just as an example, this works:

say 'Storable: ', ${ thaw 
                     freeze 
                     \(my $tst = substr 'abc', 0) };

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In reply to Re: Subtle(?) issue(?) with lvalues and serialization by Veltro
in thread Subtle(?) issue(?) with lvalues and serialization by vr

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