I see some tweets about "post-functional" as if functional were a cute trick that is passe. The world is already post-functional: imperative is post-functional: the lambda calculus is older than it all. Functional is not a cute trick: it is a profound consequence of Curry-Howard.
Maybe the key words in your answer are "none… I know". You're apparently not omniscient. Denotational semantics of "imperative" languages dates back to at least the 1970s, and was an essential stepping stone to defining the "monads" that make "pure functional" languages usable.
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