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# -*- mode: perl; -*-
# test subclassing Math::BigInt
package Math::BigInt::Subclass;
use strict;
use warnings;
use Math::BigInt;
our @ISA = qw(Math::BigInt);
our $VERSION = "0.08";
use overload; # inherit overload
# Global variables. The values can be specified explicitly or obtained from the
# superclass.
our $accuracy = undef; # or Math::BigInt::Subclass -> accuracy();
our $precision = undef; # or Math::BigInt::Subclass -> precision();
our $round_mode = "even"; # or Math::BigInt::Subclass -> round_mode();
our $div_scale = 40; # or Math::BigInt::Subclass -> div_scale();
BEGIN {
*objectify = \&Math::BigInt::objectify;
}
# We override new().
sub new {
my $proto = shift;
my $class = ref($proto) || $proto;
my $self = $class -> SUPER::new(@_);
$self->{'_custom'} = 1; # attribute specific to this subclass
bless $self, $class;
}
# We override import(). This is just for a sample for demonstration.
sub import {
my $self = shift;
my $class = ref($self) || $self;
my @a; # unrecognized arguments
while (@_) {
my $param = shift;
# The parameter "this" takes an option.
if ($param eq 'something') {
$self -> {$param} = shift;
next;
}
push @a, $_;
}
$self -> SUPER::import(@a); # need it for subclasses
}
# Any other methods to override can go here:
# sub method {
# ...
# }
1;
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