I believe the problem can be solved by changing 

my @caller = CORE::caller($i++) or return;

[download]
to 
my @caller = CORE::caller() eq 'DB'
      ? do { package DB; CORE::caller($i++) }
      : CORE::caller($i++)
   or return;

[download]

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

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