我不明白这个Perl语法,有没有人有任何想法？

Question

我从Perl插件中获得了这部分内容.我不明白它的作用.它是关联数组的数组吗？如果是这样,那么它不应该以@开头吗？任何人都可以对这个问题有所了解吗？

my $arguments =
  [ { 'name' => "process_exp",
    'desc' => "{BasePlugin.process_exp}",
    'type' => "regexp",
    'deft' => &get_default_process_exp(),
    'reqd' => "no" },
  { 'name' => "assoc_images",
    'desc' => "{MP4Plugin.assoc_images}",
    'type' => "flag",
    'deft' => "",
    'reqd' => "no" },
  { 'name' => "applet_metadata",
    'desc' => "{MP4Plugin.applet_metadata}",
    'type' => "flag",
    'deft' => "" },
  { 'name' => "metadata_fields",
    'desc' => "{MP4Plugin.metadata_fields}",
    'type' => "string",
    'deft' => "Title,Artist,Genre" },
  { 'name' => "file_rename_method",
    'desc' => "{BasePlugin.file_rename_method}",
    'type' => "enum",
    'deft' => &get_default_file_rename_method(), # by default rename imported files and assoc files using this encoding
    'list' => $BasePlugin::file_rename_method_list,
    'reqd' => "no"
  } ];

Answer 1

正如Bwmat所说,它是对一组哈希引用的引用.读

$ man perlref

要么

$ man perlreftut     # this is a bit more straightforward

如果您想了解更多有关参考文献的信息.

顺便说一句,在Perl中,您可以这样做:

@array = ( 1, 2 );          # declare an array
$array_reference = \@array; # take the reference to that array
$array_reference->[0] = 2;  # overwrite 1st position of @array

$numbers = [ 3, 4 ];        # this is another valid array ref declaration. Note [ ] instead of ( )

哈希也会发生同样的事情.

顺便说一句,在Perl中,您可以这样做:

%hash = ( foo => 1, bar => 2 );
$hash_reference = \%hash; 
$hash_reference->{foo} = 2;

$langs = { perl => 'cool', php => 'ugly' }; # this is another valid hash ref declaration. Note { } instead of ( )

并且......是的,您可以取消引用这些引用.

%{ $hash_reference }

将被视为哈希,所以如果你想打印$langs上面的键,你可以这样做:

print $_, "\n" foreach ( keys %{ $langs } );

要取消引用数组ref @{ }而不是%{ }.甚至sub可以被解除引用.

sub foo
{
  print "hello world\n";
}

my %hash = ( call => \&foo );

&{ $hash{call} }; # this allows you to call the sub foo