Functional Programming in C++ (2013)
web.archive.org
Functional Programming in C++ (2013)
1–10 of 64 posts
Re: Functional Programming in C++ (2013)
#2I just can't get behind all of this. Sure, its great to be able to reason clearly because you can see your whole state, but its exhausting always carrying your context around like a hobo with a huge backpack full of junk. Am I mistaken?
Re: Functional Programming in C++ (2013)
#3I just can't get behind all of this. Sure, its great to be able to reason clearly because you can see your whole state, but its exhausting always carrying your context around like a hobo with a huge backpack full of junk. Am I mistaken?
Exhausting is being in this situation:
object Foo {
var x: Int = 0
def bar(y: Int) = x + y
}
Re: Functional Programming in C++ (2013)
#4One difficulty with functional style c++ is just how verbose it is. Every time I tried to use std::transform (the equivalent of "map") I had to delete it and rewrite as a loop because it was just too hard to read. Functional style on a large scale is still possible.
Re: Functional Programming in C++ (2013)
#5I just can't get behind all of this. Sure, its great to be able to reason clearly because you can see your whole state, but its exhausting always carrying your context around like a hobo with a huge backpack full of junk. Am I mistaken?
The monad type-class operations carry the context around for you. You can just write in imperative-seeming do-notation. The difficult part is trying to combine monads.
Re: Functional Programming in C++ (2013)
#6I've noticed hackers/self taught prefer functional programming styles and CS degree holders prefer the more common style.
Re: Functional Programming in C++ (2013)
#7On an unrelated note, sad to see altdevblogaday has gone away :( Sure the pages are cached somewhere, but the posts always made for interesting reading.
Re: Functional Programming in C++ (2013)
#8I just can't get behind all of this. Sure, its great to be able to reason clearly because you can see your whole state, but its exhausting always carrying your context around like a hobo with a huge backpack full of junk. Am I mistaken?
Well, sort of. One of the big focuses of functional programming is _minimizing_ state; in other words, only what must be passed around should be. Sure, you'll end up having a large context that the entire program operates in, but having to pass around a context incentivizes passing around the minimal amount of context to sub-parts (functions) in the program. You don't need the whole global state? Great; only pass around a small part of it to that part of the program. You don't need the whole context all the time so you don't pass the whole thing around all the time.
Re: Functional Programming in C++ (2013)
#9This is from 2013, and the original title is "Functional Programming in C++". Moreover, Carmack never makes a statement that functional programming is the future anywhere in this article. The closest he says is "Formal systems and automated reasoning about software will be increasingly important in the future," which is a markedly different sentiment.
That said, the problem of not understanding possible code states does not seem to be purely a result of the internal software structure, but how it interacts with outside components, including the OS (if any).
There is a combinatorial explosion of the state space as a program's dependencies increase. As such, the most practical way to deal with this is crash-only software whereby components do not perform complicated error recovery, but are simply fenced and restarted to known good states with persistence used to ensure that the component can return to its prior point of operation quickly.
FP is useful for writing software like this, but not necessarily pure FP or even a single paradigm.
Re: Functional Programming in C++ (2013)
#10One difficulty with functional style c++ is just how verbose it is. Every time I tried to use std::transform (the equivalent of "map") I had to delete it and rewrite as a loop because it was just too hard to read. Functional style on a large scale is still possible.
The article is not about the functional C++ you mention. It is about using pure functions (functions that do not modify global context).