http://www.perlmonks.org?node_id=1018217


in reply to Re: what is anydbm_file?
in thread what is anydbm_file?

On trying that last little test myself, I may be misunderstanding how @ISA really works in AnyDBM_File. I tried it on a system where I know there's more than one flavor available -- because I've used at least two different ones there in the past -- but only NDBM_File shows up.
I took a look at this, and found that when AnyDBM_File is loaded, it goes through its @ISA and and replaces it with a list containing a single entry: the first module in the original @ISA list that can be successfully loaded.