Your code example, the way you use Data::Dumper to show the contents of the array allows room for misinterpretation of what is realy happening here. I feel that a better code example is the following:

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

my @ar ;
$ar[0] = undef ;
$ar[2] = 3 ;

if ( exists $ar[0] ) {
    print "0 exists\n" ;
}
if ( exists $ar[1] ) {
    print "1 exists\n" ;
}
if ( exists $ar[2] ) {
    print "2 exists\n" ;
}
if ( exists $ar[3] ) {
    print "3 exists\n" ;
}
print Dumper(\@ar) ;

[download]

This prints:

0 exists
2 exists

[download]

As you can see element 0 DOES exists when it is explicitly set to undefined. Using Data::Dumper prints:

$VAR1 = [
          undef,
          undef,
          3
        ];

[download]

In reply to Re^2: Difference between exists and defined by Veltro
in thread Difference between exists and defined by milanpwc

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