Master,
I am a newcomer for Perl. Please kindly bear with me. Why my code below: 
#!/usr/bin/perl -w
use strict;
use Data::Dumper;

my $key;
my %hoa;

while ( <DATA> )
{
   my @aoa;
   next if (/^\s+/);

   if ( /^SET/ )
   {
     my @KEY = split (/[\s:]/,$_);
     $key = $KEY[2];
   }
   elsif (/^\d/)
   {
       my @INST = split(/,/,$_);
       push @aoa, [ @INST ];
   }

       $hoa{$key} = [@aoa];
}
       print Dumper \%hoa ;

__DATA__
SET: SET1

0,100,BOOK
1,150,PENCIL
====

SET: SET2

2,110,ERASER
2,200,PEN
0,220,BLACKBOARD
1,300,CHALK
====

[download]
Fail to give this: 
$VAR1 = {
          'SET1' => [
                      [ '0','100','BOOK'],
                      [ '1','150','PENCIL'],
                    ],
          'SET2' => [
                      [ '2','110','ERASER'],
                      [ '2','200','PEN'],
                      [ '0','220','BLACKBOARD'],
                      [ '1','300','CHALK'],
                    ]
        };

[download]
Thanks so much for your patience.

In reply to Fail to update an array in HoAoA by Anonymous Monk

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