导出后，导出的变量仍然不可见

Question

我正在开发一个简单的Perl模块，用于创建和验证音符，并找到等价的音符。我将一个包含所有有效注释的数组引用存储在一个模块中，然后将其导出，以便Note.pm模块可以查看哪些注释是有效的，并在创建Note对象时对照列表进行检查。

问题是，无论我尝试什么，导出的$VALID_NOTES数组引用在Note.pm中都不可见！我已经阅读了大约一千次关于Exporter的文档，并回顾了大量使用Exporter的旧Perl模块，我只是不知道这里出了什么问题。。。

这是代码：

test.pl

use strict;
use warnings;
use Music;
my $m = Music->new();
my $note = $m->note('C');
print $note;

音乐下午

package Music;
use Moose;
use Note;
use Exporter qw(import);
our @EXPORT_OK = qw($VALID_NOTES);
no warnings 'qw';
# Valid notes
# Enharmonic notes are in preferred (most common) order:
#     Natural -> Sharp -> Flat -> Double Sharp -> Double Flat
our $VALID_NOTES = [
[ qw(C B#        Dbb) ],
[ qw(  C# Db B##    ) ],
[ qw(D       C## Ebb) ],
[ qw(  D# Eb     Fbb) ],
[ qw(E    Fb D##    ) ],
[ qw(F E#        Gbb) ],
[ qw(  F# Gb E##    ) ],
[ qw(G       F## Abb) ],
[ qw(  G# Ab        ) ],
[ qw(A       G## Bbb) ],
[ qw(  A# Bb     Cbb) ],
[ qw(B    Cb A##    ) ],
];
sub note {
my $self = shift;
my $name = shift;
return Note->new(name => $name);
}
__PACKAGE__->meta->make_immutable;

注意.pm

package Note;
use Moose;
use Music qw($VALID_NOTES);
use experimental 'smartmatch';
has 'name'  => (is => 'ro', isa => 'Str', required => 1);
has 'index' => (is => 'ro', isa => 'Int', lazy => 1, builder => '_get_index');
# Overload stringification
use overload fallback => 1, '""' => sub { shift->name() };
sub BUILD {
my $self = shift;
if (!grep { $self ~~ @{$VALID_NOTES->[$_]} } 0..$#{$VALID_NOTES}) {
die "Invalid note: '$self'n";
}
}
sub _get_index {
my $self = shift;
my ($index) = grep { $self ~~ @{$VALID_NOTES->[$_]} } 0..$#{$VALID_NOTES};
return $index;
}
sub enharmonic_notes {
my $self = shift;
my $index = $self->index();
return map { Note->new($_) } @{$VALID_NOTES->[$index]};
}
__PACKAGE__->meta->make_immutable;

当我运行代码时，我得到的输出是：

Global symbol "$VALID_NOTES" requires explicit package name at Note.pm line 15.
Global symbol "$VALID_NOTES" requires explicit package name at Note.pm line 15.
Global symbol "$VALID_NOTES" requires explicit package name at Note.pm line 22.
Global symbol "$VALID_NOTES" requires explicit package name at Note.pm line 22.
Global symbol "$VALID_NOTES" requires explicit package name at Note.pm line 29.

Answer 1

在Music.pm中，在加载Note:之前，在BEGIN块中填充@EXPORT_OK

package Music;
use Moose;
our @EXPORT_OK;
BEGIN { @EXPORT_OK = qw($VALID_NOTES) }
use Exporter qw(import);
use Note;