Why do you use TRUE and FALSE constants? Perl already has some sense of true and false ("", "0", 0 and undef are false, all other values are true).
If you ever need a representation in terms of 1 or 0, just use ?:.

$foo ? 1 : 0;
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(Or the more evil !!$foo || 0 :))

2;0 juerd@ouranos:~$ perl -e'undef christmas'
Segmentation fault
2;139 juerd@ouranos:~$
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