0:59 >perl -Mstrict -MData::Dump -MConst::Fast -we "use constant A => 12; const our $B => 13; my %h = ( (A) => 'twelve', $B => 'thirteen'); dd \%h;" { 12 => "twelve", 13 => "thirteen" } 0:59 >perl -Mstrict -MO=Deparse -MData::Dump -MConst::Fast -we "use constant A => 12; const our $B => 13; my %h = ( (A) => 'twelve', $B => 'thirteen'); dd \%h;" BEGIN { $^W = 1; } use strict; use Data::Dump; use Const::Fast; use constant ('A', 12); &const(\our $B, 13); my(%h) = (12, 'twelve', $B, 'thirteen'); dd(\%h); -e syntax OK 0:59 > #### use constant DEBUG => 0; ... perform_some_debugging_operation() if DEBUG; ...