if (defined $hash->{A}->{LEVEL2}->{LEVEL2_2}) {
To prevent autovivification, make this 
if (exists $hash->{A} && exists $hash->{A}->{LEVEL2} && defined $hash-
+>{A}->{LEVEL2}->{LEVEL2_2}) {

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In reply to Re: usage of if on nested hash creating empty slot for non existing value by bart
in thread usage of if on nested hash creating empty slot for non existing value by rakeshrocks

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