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fbrm@monastery:~$ perl -MData::Dumper -E '$Q=$A[4][6]; say Dumper \@A' $VAR1 = [ ... undef, [] ];
fbrm@monastery:~$ perl -MData::Dumper -E '$A[4]="hi"; say Dumper \@A' $VAR1 = [ ... undef, 'hi' ];