In the C++20 there is written relative to std::conjunction
 
5 The specialization conjunction has a public and unambiguous base that is either
(5.1) — the first type Bi in the list true_type, B1, . . . , BN for which bool(Bi::value) is false, or
(5.2) — if there is no such Bi , the last type in the list.
 
But in my point of view there is nothing said what will be if the template argument list is empty.
 
With best regards
(Vlad from Moscow)
 
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