I'm saying his characterization of promises as functional is so close to being right that it's the worst kind of wrongness.

It's worse to say, "The capital of Kenya is Nairobi Central" than to say "The capital of Kenya is London." It is worse because errors that are only slightly wrong and maybe even partially correct are more deceptive, durable, and confusing.

A promise is not a functional concept. Functions don't make promises. You CAN, as a thinking human, re-conceptualize the immutable return value of a function as being "pretty much the same" as a promise, but when you re-conceptualize functional programming you are just deconstructing what is already understood to be an arbitrary conceptual construct. Any conceptual construct--especially one based on simple metaphors--can be deconstructed into some other form. This doesn't invalidate the construct and it doesn't equate the construct as such with the deconstructed components.

You might as well say that an airplane is not really an airplane. It's just two wings, a cockpit, some jet engines and a fuselage assembled together in a certain way so that it can fly. It's not really an airplane; it's just those things in that way. And those things are really just all made out of aluminium so really it's not an airplane it's just aluminium. Anyone who says an airplane is more than just aluminium is making a tyrannical dichotomy.

So according to you promises are functional because under the hood promises have some conceptual similarity to the immutable return values provided in functional programming. But under the hood the Boeing 737 is just scrap metal. Yet it's NOT just scrap metal. The difference is that "the promise" is a precise concept based on some metaphors that is specifically used in declarative styles and not in functional styles. Functions return immutable values. Declarations make promises. Under the hood there may be similarities but no one made any claims to the contrary.

If people don't think these high level conceptual distinctions are important, why are they even reading this article that is entirely about splitting hairs between these conceptual distinctions? AND the article is even getting it wrong because the author is a self-admitted amateur. Why bother learning from the village loudmouth when there are geniuses who publish books and give lectures just down the hall?

The stuff that reaches the front page of HN makes no sense. Most of it is written by terribly ignorant people. Programmers have no respect for expertise.