rbi has asked for the wisdom of the Perl Monks concerning the following question:

Hello,
This code:
use strict;
use warnings;
use XML::Simple;use Data::Dumper;
my $file = './test.xml';
my %tmp = ( 'A' => [ [1] ]);
XMLout(\%tmp,outputfile=>$file);
%tmp = %{XMLin($file,forcearray=>['A'])};
warn Dumper(\%tmp);

%tmp = ( 'A' => [ [1,2] ]);
XMLout(\%tmp,outputfile=>$file);
%tmp = %{XMLin($file,forcearray=>['A'])};
warn Dumper(\%tmp);

[download]
outputs:
$VAR1 = {
          'A' => [
                   {
                     'anon' => '1'
                   }
                 ]
        };
$VAR1 = {
          'A' => [
                   [
                     '1',
                     '2'
                   ]
                 ]
        };

[download]
How do I force the value of key A to be an array of array also in the first case ?
Thank you.

Replies are listed 'Best First'.
Re: Forcing to anonymous array in XML::simple
by grep (Monsignor) on Dec 14, 2006 at 15:54 UTC
    The problem you are having is the element you are forcing to an array (A) is an array. But you're wanting ForceArray to cascade down to the children of A. Since the first element of A is a ref, it is unnamed and XML::Simple says it only takes names (or '1') in the ForceArray option.

    You need to turn on ForceArray for the entire thing

    use strict;
use warnings;
use XML::Simple;use Data::Dumper;
my $file = './test.xml';
my %tmp = ( 'A' => [ [1] ]);
XMLout(\%tmp,outputfile=>$file);
%tmp = %{XMLin($file,forcearray=>1};
warn Dumper(\%tmp);

%tmp = ( 'A' => [ [1,2] ]);
XMLout(\%tmp,outputfile=>$file);
%tmp = %{XMLin($file,forcearray=>1)};
warn Dumper(\%tmp);

    [download]
    Outputs: 
    $VAR1 = {
          'A' => [
                 [
                   '1'
                 ]
               ]
        };
$VAR1 = {
          'A' => [
                 [
                   '1',
                   '2'
                 ]
               ]
        };

    [download]

    grep
    1)Gain XP 2)??? 3)Profit

[reply]
[d/l]
[select]
      Thank you.
      I have one more question. I tested more pairs in the hash and the option noattr=>1 (that I realized I need to use). When I run:
      use strict;
use warnings;
use XML::Simple;use Data::Dumper;
my $file = './test.xml';

my %tmp = ( A => [ [1] ], B => 1);
XMLout(\%tmp,outputfile=>$file,noattr=>1);

%tmp = %{XMLin($file,forcearray=>['A'],noattr=>1)};
warn Dumper(\%tmp);

%tmp = %{XMLin($file,forcearray=>1,noattr=>1)};
warn Dumper(\%tmp);

      [download]
      I get:
      
$VAR1 = {
          'A' => [
                   {
                     'anon' => '1'
                   }
                 ],
          'B' => '1'
        };
$VAR1 = {
          'A' => [
                   [
                     '1'
                   ]
                 ],
          'B' => [
                   '1'
                 ]
        };

      [download]
      is it correct that I cannot get A value as array and B value as scalar ?, i.e.:
      $VAR1 = {
          'A' => [
                   [
                     '1'
                   ]
                 ],
          'B' => '1'
        };

      [download]
[reply]
[d/l]
[select]
        Yes, B will also be forced into a 1 element array (with ForceArray => 1). But IMO that is the way it should be. It's consistant.

        grep
        1)Gain XP 2)??? 3)Profit

[reply]
[d/l]

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