No, it depends on what you're doing. Always does, always will.
> Even in ... GUI programming, ... OO is a failure because interactive programs are extremely concurrent
Seems to work well for me on windows. What's the problem precisely?
> And functional programming is no good as a general programming paradigm because ... Little of computing--almost nothing--is declarative
That's just wrong.
> Programming cannot be married to mathematics...
You give no evidence despite it being a long association.
> Thinking being able to easily execute your declarative programs in parallel means you'll never have to think concurrently
Yes, because concurrency only becomes an obvious issue when state is involved. So FP sidesteps that by not having interacting state. I have some criticisms of FP but this is plain silly.
You're just dissing stuff here. It's annoying.
* Artificial general intelligence * Operating systems * Video games * Emulators for hardware * Interpreters * Debuggers * Word editors * Image editors * Graphical user interfaces * Robotics * Web browsers * Servers
Basically everything that makes computing interesting is non-declarative and concurrent. Financial math on K street, parser combinators, and SQL queries are the declarative segment of programming.
Declarative/imperative are models, not necessarily implementations (although they often are treated as model x = implementation x). You need to separate the two conceptually, but in implementation you can do both. Anything you can do declaratively you can do imperatively and the reverse.
As such it makes it meaningless to say that almost nothing is declarative because how you choose to create it is a choice. How well it runs is another matter because real hardware is relentlessly state-y, but that's an implementation issue. And that's fine, and sometimes imperative stuff is just cleaner.
But you can write a web browser or a GUI or whatever declaratively, but underneath it will be imperative because that's hardware.
Declarative vs imperative is a choice, not necessarily a 'natural' thing, (depending on the problem, I'd say a web page renderer is distinctly stateless - take some static HTNL, render it, where's the state?). A web server can be stateless too, a request comes in, a web page goes out. I need someone else to speak for others, pretty sure stateless GUIs have been written.
Any big data cruncher that works on petabytes, purely with output coming from input deterministically is effectively stateless.
> “oh, that’s obviously stateful and imperative” merely because they haven’t thought about the problem in a different way.
No I am not a conventionalist.
Since turing machines are turing complete, and existing general purpose CPUs are turing complete, this is trivially incorrect.
> That's why computer scientists invented I/O automata ... those items on my list
wat?
Where it's needed such as in modelling the very important implementation detail of parallelism on multi-core machines to ensure correctness (such as with model checkers like Spin) then stuff like buchi automata are used, but that's dragging maths into the real world to solve real world problems. Turing machines don't live in the real world.
Please just stop.
But this is all naval-gazing anyway. What's even the point of a purely-declarative OS when it's either gonna:
1. Act as a glorified C preprocessor for an imperative language like Haskell and its do-notation?
2. Look like brainfuck?
Typically declarative systems are interesting because it is easier to prove strong properties about them.
Imperative programs are so popular among "joe schmoe" average programmers because they have a clear teleology. People are willing to forgive that imperative programs are harder to formally reason about because they make the teleology clearer. But have you seen declarative code? Because it's like math formulas, each function needs the same kind of documentation in order to understand the teleology behind the function.
Even the Xerox manuals contain several examples.
I must say that I have trouble reconciling this with the fact that every single GUI program running on my computer right now is written mostly in C++ with a bit in C for my WM and a bit of Rust for Firefox.
But more from a user developer point of view. Power user.. power users aren’t here anymore
And functional programming is no good as a general programming paradigm because:
1. Little of computing--almost nothing--is declarative. That means functional programming's non-general by definition.
2. Programming cannot be married to mathematics despite what formal proof proponents and people who think naming their language "Pascal" is a good idea think. It will always be an arranged and sham marriage.
3. Thinking being able to easily execute your declarative programs in parallel means you'll never have to think concurrently and can just outsource everything to Hadoop only means you can't understand the difference between parallelism and concurrency.