croak 'The first argument must be a hash reference to the %SIG hash'
unless $sig and ref $sig eq 'HASH';
my $self = bless $class->SUPER::new(@_), $class;
croak 'The first argument must be a hash reference to the %SIG hash'
unless $sig and ref $sig eq 'HASH';
my $self = bless $class->SUPER::new(@_), $class;