it obviously has something to do with $hasarg

No, it has to do with @DB::args.

I'm not sure why Carp think it's being overridden incompletely

It seems to indicate @DB::args needs to be adjusted somehow to compensate for the fact that caller isn't being called from where the user thinks it is being called.

[Update: The check was introduced by this commit. Read the commit message for some info. ]

The OP code is drawn from 5.14.2, but I have the same issues in 5.12.4, and the Carp code is a bit simpler there:

That's because code was added to 5.14 to identify where the bad code is located ($where).

In reply to Re: Trying to understand (caller($i))[4], a.k.a. $hasargs [diagnostic] by ikegami
in thread Trying to understand (caller($i))[4], a.k.a. $hasargs by Oberon

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