I've searched through the documentation of Combine and looked at all the WWDC videos, and nowhere does Apple mentioned anything about "Reactive Programming". Apple states that
The Combine framework provides a declarative Swift API for processing values over time.
Prior to this, RxSwift, which is an implementation of Reactive Extensions standard, offered abstractions to facilitate reactive programming. I know there are varying descriptions of "reactive programming" itself, but let's constrain it to "a paradigm that deals with data streams and propagation of state change" (as described by Wikipedia).
This is more a question about personal curiosity than it having any tangible impact, but I wanted to check if anyone knew the background behind why Apple chose not to attribute Combine to Reactive Programming. I know Combine is more closely aligned with Reactive Streams, but that standard still falls under the "Reactive Programming" umbrella.
Although Combine (esp as used in SwiftUI) is considered to be somewhat “reactive”, one can infer from Apple’s scrupulous avoidance of the term that this is a conscious decision, despite the obvious parallels. I am unclear as to what degree this was to avoid baggage associated with the term, the fact that they don’t follow reactive patterns/syntax slavishly, and to what degree it was a marketing decision or an attempt to use more accessible terminology.
I suspect that your own web searches for “apple combine reactive” will yield lots of hits.
My apologies, but I think some of my links may be behind paywalls, but you can see that while the industry sees this as Apple’s reactive-like framework, Apple studiously avoids the using the term.
As an aside, in Apple’s swift-async-algorithms, they make repeated references to analogous reactive API (e.g., see CombineLatest). So, they’re clearly conscious about drawing parallels between Combine and reactive libraries.