I seem to remember reading somewhere (ie I might be wrong), that due to the magic nature of typeglobs and the punctuation variables, that you can't just get a single type for each. That probably isn't too clear, it's easier with an example: Since Perl wants $_, you also get %_, @_ and &_ for free.

My (very limited) testing demonstrates that that's the case for other punctuation variables, too:

use strict;
use warnings;
use Data::Dumper;

# $\ - output record separator
%\ = ( 1 => 2);
@\ = ( 1, 2 );
print Dumper \%\, \@\;;

# $@ - eval error
%@ = ( 3 => 4);
@@ = ( 3, 4 );
print Dumper \%@, \@@;
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