No there isn't, but a constant is merely 
sub Ro:Sham::Bo::DEBUG(){ !!1 }
sub Ro:Sham::Bo::DEBUG(){ !!0 }
package Ro:Sham::Bo;
use constant DEBUG => !!$ENV{PERL_RO_SHAM_BO};

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In reply to Re: defining constant in other package by Anonymous Monk
in thread defining constant in other package by LanX

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