> In fact, most features you associate with FP were very well known when OOP came about.
That's true, even though OOP as a paradigm was articulated before FP was (both paradigms were prefigured by less-structured practices in programming, before either was articulated as a programming paradigm, so the techniques of both existed before either was cataloged as a paradigm.)
> So OOP and FP have never been in opposition to one another. Just sets of features that you can choose from.
OOP and FP aren't sets of features, they are approaches to programming; there are features of languages which facilitate FP and/or OOP, to be sure, but the paradigms aren't sets of features.
> As to non-OOP FP, it is quite possible that much of its allure is nothing more than its relative novelty to developers today,
I doubt it; non-OOP FP has been around almost as long as OOP has been, has frequently played a fairly central role (whether or not it was explicitly named as a paradigm) in computer science in education, and, in any case, and it became popular when domains where it particular implementations of it had long been proven (particularly, concurrent/distributed systems) started becoming part of the problem space of mainstream development.
The idea that its popularity is driven primarily by novelty doesn't seem like the best explanation.
> has frequently played a fairly central role (whether or not it was explicitly named as a paradigm) in computer science in education
Yes, but not a big role in OOP's home court: large systems with long lifespans.
> The idea that its popularity is driven primarily by novelty doesn't seem like the best explanation.
I didn't say that. I said that the low number of reported problems is likely a result of it not having seen much actual combat and coming under heavy enemy fire just yet (namely, large projects, maintenance over many years, some by inexperienced programmers). It's still fresh out of basic training (in comparison to OOP). OOP also seemed almost perfect for quite a few years.
That's true, even though OOP as a paradigm was articulated before FP was (both paradigms were prefigured by less-structured practices in programming, before either was articulated as a programming paradigm, so the techniques of both existed before either was cataloged as a paradigm.)
> So OOP and FP have never been in opposition to one another. Just sets of features that you can choose from.
OOP and FP aren't sets of features, they are approaches to programming; there are features of languages which facilitate FP and/or OOP, to be sure, but the paradigms aren't sets of features.
> As to non-OOP FP, it is quite possible that much of its allure is nothing more than its relative novelty to developers today,
I doubt it; non-OOP FP has been around almost as long as OOP has been, has frequently played a fairly central role (whether or not it was explicitly named as a paradigm) in computer science in education, and, in any case, and it became popular when domains where it particular implementations of it had long been proven (particularly, concurrent/distributed systems) started becoming part of the problem space of mainstream development.
The idea that its popularity is driven primarily by novelty doesn't seem like the best explanation.