What I want to test for is like Is the underlying implementation of this blessed thing a hashref?

reftype($ref) eq 'HASH' answers that question.
reftype can be found in core module Scalar::Util.

UNIVERSAL::isa($ref, 'HASH') also answers that question.
isa is always present. It's documented in core module UNIVERSAL.

...but is it the right question? Shouldn't you be asking "Can this ref be used as a hashref?"

eval { %$ref || 1 } will answer that question. 

if (eval { %$ref || 1 }) {
   # Hash
   ...
} elsif (eval { @$ref || 1 }) {
   # Array
   ...
} else {
   ...
}

[download]

Update: Added isa.

In reply to Re: Blessing interior hashes by ikegami
in thread Blessing interior hashes by throop

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