Anonymous Monk has asked for the wisdom of the Perl Monks concerning the following question:

I know that the Math::BigInt objects can be printed with "print": 
use Math::BigInt;
print Math::BigInt->new("123"); # prints "123"

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However, when I try to print an object that I create, it just prints something like the following: MyClass=HASH(0x9eff760) My question is, how do I tell it how to print objects of my class?

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Re: How to make object printable
by tilly (Archbishop) on Mar 01, 2009 at 00:58 UTC
    Use overload to provide a stringification method for objects of your class. Then when you print them they will stringify using that method.
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Re: How to make object printable
by Anonymous Monk on Mar 01, 2009 at 01:59 UTC
    Here's a very basic example to get you started:
    package ClassPrintable;
use overload q{""} => sub { return shift->stringify() };

sub new {
  my ($class,$args) = @_;
  return bless($args,$class);
}

sub stringify {
  my $self = shift;
  my $ret = "{";
  for (sort keys %$self){
    $ret .= " $_ : ".$self->{$_}.",";
  }
  chop($ret) if (keys %$self);
  return "$ret".' }';
}

package main;

my $c = ClassPrintable->new({a =>1,b=>2,c=>3});
print $c;

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