In terms of workarounds ...

For the benefit of the novice PerlMonk, it should be emphasized that none of the workarounds address (nor, I'm sure, were intended to address) the total mutability of the content of "constant" references: 

c:\@Work\Perl\monks>perl -wMstrict -MData::Dump -le
"use constant { ONE => 1, FOUR => 4 };
 use constant AREF => [ ONE .. FOUR ];
 dd AREF;
 ;;
 AREF->[3] = 99;
 dd AREF;
 ;;
 AREF->[9] = 999;
 dd AREF;
 ;;
 $#{ +AREF } = -1;
 dd AREF;
"
[1, 2, 3, 4]

[1, 2, 3, 99]

[1, 2, 3, 99, undef, undef, undef, undef, undef, 999]

[]

[download]
A search of MetaCPAN for "lock" yields a couple of interesting-looking modules, neither of which have I used and so cannot recommend: Data::Lock and Array::Lock.

In general, Perl handles the important concept of immutability very poorly. I have the vague notion that Perl 6 does better in this respect; can anyone comment?

Give a man a fish:  <%-{-{-{-<

In reply to Re^2: Using hashref values in constant declarations. by AnomalousMonk
in thread Using hashref values in constant declarations. by nameofmyuser

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