package Foo;

sub new {
    my $class = shift;
    my %options = @_;

    my $self = {};

    # Do 1000 lines of stuff with %options

    return bless $self, $class;
}

package Bar;

use base 'Foo';
# A bunch of stuff goes here, but NO new() method!

package main;

my $object = Bar->new(
    # A bunch of named parameters go here
);

##</code><code>##

package My::Base::Class;

sub new
{
    my $class = shift;

    my $self = bless {}, $class;

    (@_ % 2) && die "Odd number of parameters passed to new()";
    my %options = @_;

    while (my ($k, $v) = each %options)
    {
        next unless $self->can($k);
        $self->$k($v);
    }

    return $self;
}