Re: Truthfulness of references

To my initial surprise, the code above printed "We have a hash reference.", even though the hash I've referenced is empty ( ie: no keys and no values ).

No matter how many keys it hash, it's still a hash. ref(\%hash) returns HASH, which is a true value. if (%$hash_ref) will tell you if the referenced hash is empty or not.

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Re^2: Truthfulness of references by njcodewarrior (Pilgrim) on Mar 13, 2007 at 11:15 UTC
Thanks ikegami. So I should use: `if ( %$hash_ref )` to check whether the hash is empty or not? By the way, thanks for your reply on this. I haven't used the Chatterbox before, so I wasn't sure how to respond ( I've been meaning to read up on it, but haven't found the time ). njcodewarrior	[reply] [d/l]
Re^3: Truthfulness of references by ikegami (Patriarch) on Mar 14, 2007 at 07:12 UTC
Yes, when `$hash_ref` holds a reference to a hash. If `$hash_ref` doesn't hold a reference to a hash, you'll get a warning or a runtime error depending on what it holds and whether `use strict 'refs';` is active or not.	[reply] [d/l] [select]