PPC0014 contains this example:
my %signals = %SIG;
my %signals = %{^SIG};
which seems to imply we also want control character versions of the alphabetical Perl variables.
I've compiled the full list from perlvar, and came up with this list:
$a, $b, %ENV, @F, @INC, %INC, $INC, @ISA, %SIG, $ARGV, @ARGV.
Does this imply that the corresponding control character variables should exist? Namely:
$^a, $^b, %{^ENV}, @^F, @{^INC}, %{^INC}, ${^INC}, @{^ISA}, %{^SIG}, ${^ARGV}, @{^ARGV}.