UPDATE: Wait a minute, that doesn't quite work.
UPDATE 2: Okay, works now. That first sentence in my original post should have been: "Take @arr out of the while loop, clear @arr every time you get a new key, and you're good to go."

**********

Get rid of @arr out of the while loop, clear @arr every time you get a new key, and you're good to go.

You might also want to change @INST and @KEY to @inst and @key, since by convention capital variable names are constants: perlstyle. (Some people also use capitals to indicate globals, though pelstyle suggests using mixed case to do this.) 

#!/usr/bin/perl -w
use strict;
use warnings;

use Data::Dumper;

my $key;
my %hoa;

my @arr;
while ( <DATA> )
{   
   next if (/^\s+/);
   if ( /^SET/ ) {
     my @KEY = split (/[\s:]/,$_);
     $key = $KEY[2]; 
     @arr = (); # need to do this or get extra elements in second arra
+y. Try commenting this out... interesting
   } elsif (/^\d/) {
       my @INST = split(/,/,$_);
       push @arr, [@INST];
    }
   $hoa{$key} = [ @arr];
}
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]

In reply to Re: Fail to update an array in HoAoA by tphyahoo
in thread Fail to update an array in HoAoA by Anonymous Monk

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