It's still the same deal. Your hash element has been autovivified and set to undef. This is what the warning is - you are using the undef as a number. If your hash had not been autovivified, your would have received a "Expected reference...." error when trying to access the value.

The way you have avoided the warning is the correct way to do it, although you can be slightly more compact with:

$self->{hash}{$subject} ||= 0;

[download]

In summary, you are trying to fix the wrong problem. Perl isn't being tricky this time. All it's doing is warning you that it is turning an 'undef' into a '0' for the addition. This is what you want.

____________________
Jeremy
I didn't believe in evil until I dated it.

In reply to Re: Re: Autovivification not working? by jepri
in thread Autovivification not working? by Juerd

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