Code rewrite

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

my @a = (1..1284);

my $chunkedRef = chunky(@a);

sub chunky {
     #for chunks (chunks = 100 blocks of passed -in array)            
+                                                                     
+    
     my %master;
     for(0..int @_/100)
     {
         # create an array for each 100 elements and add it to the has
+h                                                                    
+    
         push @{$master{$_+1 . ' key'}},@a[$_*100..$_*100+100];
     }

     return \%master;
}

print Dumper %$chunkedRef;
1;
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