See autovivification, a pragma (available from CPAN) that can lexically disable autovivification (the behavior). Here's an example from perlfaq4:

{
    no autovivification;
    my %hash;
    if( exists $hash{key1}{key2}{key3} ) {
        ...;
    }
}

[download]

The faq also suggests a few other techniques.


Dave

In reply to Re: Undesirable parent hash keys by davido
in thread Undesirable parent hash keys by sophate

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