use strict;
use warnings;
use Math::Pari;

my %zero;
my %zero_dot;
my %delta;

@zero    { qw( perl pari ) } = ( 0  ) x 2;
@zero_dot{ qw( perl pari ) } = ( 0. ) x 2;

$delta{ perl } =       1./7E300  ;
$delta{ pari } = PARI( 1./7E300 );

$zero    { perl } += $delta{ perl };
$zero_dot{ perl } += $delta{ perl };

$zero    { pari } += $delta{ pari };
$zero_dot{ pari } += $delta{ pari };

print '     $delta{ perl }: ', $delta   { perl }, $/;
print '0  + $delta{ perl }: ', $zero    { perl }, $/;
print '0. + $delta{ perl }: ', $zero_dot{ perl }, $/;
print $/;
print '     $delta{ pari }: ', $delta   { pari }, $/;
print '0  + $delta{ pari }: ', $zero    { pari }, $/;
print '0. + $delta{ pari }: ', $zero_dot{ pari }, $/;
__END__
     $delta{ perl }: 1.42857142857143e-301
0  + $delta{ perl }: 1.42857142857143e-301
0. + $delta{ perl }: 1.42857142857143e-301

     $delta{ pari }: 1.428571428571428547E-301
0  + $delta{ pari }: 1.428571428571428547E-301
0. + $delta{ pari }: 0.E-92