Anyway, I can't get it to run

As others have explained, switch our $O //= 2 to our $O ||= 2 for pre-5.10 perls.

I have to admit this code is too complex for me - too many shortcuts

If you have specific questions about particular lines of code, just ask. That is what this place is for.

Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
"Science is about questioning the status quo. Questioning authority".
In the absence of evidence, opinion is indistinguishable from prejudice.
RIP an inspiration; A true Folk's Guy

In reply to Re^3: Storing large data structures on disk by BrowserUk
in thread Storing large data structures on disk by roibrodo

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