Using exists on array elements makes no sense. The information it returns is useless. 

my @a;
$a[1] = undef;
$a[2] = 'foo';

print("0: ", exists($a[0]) ?1:0,"\n");  # 0
print("1: ", exists($a[1]) ?1:0,"\n");  # 1
print("3: ", exists($a[3]) ?1:0,"\n");  # 0

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exists $a2[$i] should be $i < @a2 or defined $a2[$i] depending on what you were trying to accomplish.

In reply to Re^2: compare values within hash by ikegami
in thread compare values within hash by Anonymous Monk

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