please compare 
  DB<30> x map { $_ = 1 } 2
Modification of a read-only value attempted at (eval 40)[c:/Perl_524/l
+ib/perl5db.pl:737] line 2.
  DB<31>

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Cheers Rolf
(addicted to the Perl Programming Language :)
Wikisyntax for the Monastery

In reply to Re^2: Shouldn't references be readonly? by LanX
in thread Shouldn't LITERAL references be readonly? (updated) by LanX

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