需要了解关于课程的一些事情

假设我上课了

package Person;
# Class for storing data about a person
#person7.pm
use warnings;
use strict;
use Carp;
my @Everyone;
sub new {
   my $class = shift;
   my $self = {@_};
   bless($self, $class);
   push @Everyone, $self;
   return $self;
}
# Object accessor methods
sub address { $_[0]->{address }=$_[1] if defined $_[1]; $_[0]->{address } }
sub surname { $_[0]->{surname }=$_[1] if defined $_[1]; $_[0]->{surname } }
sub forename { $_[0]->{forename}=$_[1] if defined $_[1]; $_[0]->{forename} }
sub phone_no { $_[0]->{phone_no}=$_[1] if defined $_[1]; $_[0]->{phone_no} }
sub occupation {
   $_[0]->{occupation}=$_[1] if defined $_[1]; $_[0]->{occupation}
}
# Class accessor methods
sub headcount { scalar @Everyone }
sub everyone { @Everyone}
1;

而我这样打电话

#!/usr/bin/perl
# classatr2.plx
use warnings;
use strict;
use Person;
print "In the beginning: ", Person->headcount, "\n";
my $object = Person->new (
   surname=> "Galilei",
   forename=> "Galileo",
   address=> "9.81 Pisa Apts.",
   occupation => "Philosopher"
);
print "Population now: ", Person->headcount, "\n";
my $object2 = Person->new (
   surname=> "Einstein",
   forename=> "Albert",
address=> "9E16, Relativity Drive",
occupation => "Theoretical Physicist"
);
print "Population now: ", Person->headcount, "\n";
print "\nPeople we know:\n";
for my $person(Person->everyone) {
   print $person->forename, " ", $person->surname, "\n";
}

输出继电器

>perl classatr2.plx
In the beginning: 0
Population now: 1
Population now: 2
People we know:
Galileo Galilei
Albert Einstein
>

怀疑 - >我对这部分代码有疑问

for my $person(Person->everyone) {
   print $person->forename, " ", $person->surname, "\n";
}

查询 - >这里$ person是一个哈希引用.为什么我们这样称呼$person->forename.而散列引用应该被称为$person->{$forename}