http://www.perlmonks.org?node_id=11104864


in reply to Insert into element into arrays ref

No need to futz around with map. Just push the contents of @{$data2} onto @{$data1}.

The cake is a lie.
The cake is a lie.
The cake is a lie.

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Re^2: Insert into element into arrays ref
by Anonymous Monk on Aug 22, 2019 at 18:43 UTC
    Using push:

    push @$data1, @$data2;

    Result:
    [
          {
            'DATE' => '2009-05-05',
            'NAME' => 'PAUL DY',
            'NUMBER' => '00001'
          },
          {
            'NAME' => 'ANTHONY RD',
            'NUMBER' => '00003',
            'DATE' => '2012-01-07'
          },
          {
            'NUMBER' => '00023',
            'NAME' => 'RUTH RD',
            'DATE' => '2018-01-07'
          },
          {
            'CODE' => 'X11'
          }
        ]

    [download]

    Looking for this:
    [
{
   'NAME' => 'PAUL DY',
   'DATE' => '2009-05-05',
   'NUMBER' => '00001',
   'CODE' => 'X11',
 },
   {
   'NAME' => 'ANTHONY RD',
   'DATE' => '2012-01-07',
   'NUMBER' => '00003',
   'CODE' => 'X11',
 },
  {
   'NAME' => 'RUTH RD',
   'DATE' => '2018-01-07',
   'NUMBER' => '00023',
   'CODE' => 'X11',
 },
 
 ]

    [download]

    Thanks!
[reply]
[d/l]
[select]

      One way (update: see the Perl Data Structures Cookbook): 

      c:\@Work\Perl\monks>perl
use strict;
use warnings;

use Data::Dumper;

my $data1 = [
{
   'NAME' => 'PAUL DY',
   'DATE' => '2009-05-05',
   'NUMBER' => '00001',

 },
   {
   'NAME' => 'ANTHONY RD',
   'DATE' => '2012-01-07',
   'NUMBER' => '00003',
 },
  {
   'NAME' => 'RUTH RD',
   'DATE' => '2018-01-07',
   'NUMBER' => '00023',
 },

 ];

my $data2 = [
  {
    'CODE' => 'X11',
  }
];

foreach my $hashref (@$data1) {
  %$hashref = (%$hashref, %{ $data2->[0] });
  }

print Dumper $data1;

__END__
$VAR1 = [
          {
            'NAME' => 'PAUL DY',
            'DATE' => '2009-05-05',
            'CODE' => 'X11',
            'NUMBER' => '00001'
          },
          {
            'NAME' => 'ANTHONY RD',
            'DATE' => '2012-01-07',
            'CODE' => 'X11',
            'NUMBER' => '00003'
          },
          {
            'NAME' => 'RUTH RD',
            'DATE' => '2018-01-07',
            'CODE' => 'X11',
            'NUMBER' => '00023'
          }
        ];

      [download]

      Update 1: Note that using this method, if there is a key in the hash referent of the single element of the  $data2 array referent that is the same as one in a hash referent of any  $data1 array referent, the value of the former will silently overwrite the value of the latter. (Update: For instance, see what happens if  $data2 happens to be
          my $data2 = [ { 'CODE' => 'X11',  'NAME' => 'JONES', } ];
      instead. (Update: This exact problem is discussed more clearly in the FAQ referenced by BillKSmith here.))

      Update 2: Here's a testing framework for playing around with other approaches. See Test::More, Test::NoWarnings.

      Read more... (2 kB)

      Give a man a fish:  <%-{-{-{-<

[reply]
[d/l]
[select]
      You are merging the hash in $data2 with each of the hashes in $data1. Read the FAQ. 
      perldoc -q "How do I merge two hashes?"

      [download]
      Bill
[reply]
[d/l]

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