In a recent thread it was shown that hash slices are not faster than maps, exists on hash slices is not needed. 

sub slex { my $h = shift; return map { exists $h->{$_} || 0 } @_ }

my %h = map { $_ => 1 } 'a'..'t';
my @bool = slex \%h, 'a'..'z';
print "@bool\n";

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In reply to Re^3: Something eq hashref key by hdb
in thread Something eq hashref key by Anonymous Monk

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