Perl：如何訪問傳遞給子例程的哈希數組

Question

讓一個perl腳本從xml讀取，將數據解析爲一個子哈希，輸出哈希數組，然後從主調用第二個子數組來處理數組的哈希。

Data :: Dumper顯示一切正常通過。

有一個可怕的時間搞清楚爲什麼我現在不能訪問哈希。

use strict; 
use warnings; 
use Data::Dumper; 

my (@sortedData, $value1, $value2); 
use subs qw(processData outputData); 

@sortedData = processData; 
outputData($value1, $value2, \@sortedData); 

sub processData{ 
    # Example code 
    # # Does some processing of xml that results in a hash. 
    # # That series of hashes is pushed onto an array 
    my ($item, @results); 

    # foreach $item (@{ $rss->{items}){ 
    # my %data = (
    #  'first' => $item->{'value'}, 
    #  'second' => $item->{'value'}, 
    #  'third' => $item->{'value'} 
    # ); 

    # push @results, \%data; 
    # } 
    # Essentially the hash is : 

    @results = (
     {'data1'=>810,'data2'=>153,'data3'=>215}, 
     {'data1'=>160,'data2'=>220,'data3'=>604}, 
     {'data1'=>940,'data2'=>103,'data3'=>115}, 
     {'data1'=>100,'data2'=>319,'data3',525}, 
     {'data1'=>500,'data2'=>803,'data3'=>650} 
     ); 
    return @results; 
} 

sub outputData{ 
    my ($input1, $input2, @localData) = @_; 
    print Dumper @localData; 

    print "\@localData: " . @localData . "\n"; 
    foreach my $i (@localData){ 
    # foreach my $j ($i){ 
    #  print $i . "\n" . $j . "\n"; 
    # } 
     print "\$i: " . $i . "\n"; 
    } 
} 

輸出：

$VAR1 = [ 
      { 
      'data3' => 215, 
      'data2' => 153, 
      'data1' => 810 
      }, 
      { 
      'data3' => 604, 
      'data2' => 220, 
      'data1' => 160 
      }, 
      { 
      'data2' => 103, 
      'data3' => 115, 
      'data1' => 940 
      }, 
      { 
      'data1' => 100, 
      'data3' => 525, 
      'data2' => 319 
      }, 
      { 
      'data1' => 500, 
      'data3' => 650, 
      'data2' => 803 
      } 
     ]; 
@localData: 1 
$i: ARRAY(0x80071b30) 

我不理解爲什麼@localData的值是1或爲什麼@localData的元件的參考是數組，而不是HASH。

我當然是第一次測試我對PERL數組的更深入的理解。 我不像我想的那麼瞭解它。

Answer 1

您將參考傳遞給數組，然後將此單個標量分配給@localData。修復：

sub outputData{ 
    my ($input1, $input2, $localData) = @_; 
    print Dumper $localData; 

    print "\@localData: " . @$localData . "\n"; 
    foreach my $i (@$localData){ 
     ... 
    } 
}