`f(a, b)` looks like a call to a function that takes a single tuple as its argument. So I would expect `f` to have the type signature `A * B -> C` instead of `A -> B -> C`. Is my intuition wrong? If it is, then what does F# use the parenthetical syntax for?

[1] https://learn.microsoft.com/en-us/dotnet/fsharp/language-ref...

F# enforcing a lot of good practice code style stuff (order matters for example pisses off long time devs who already have styles, but prevents SOOOO much stupid bs from beginners) and basically eliminates runtime/chasing variable state errors completely so long as you can stay within style. Yes it'd be nicer if there was only one way to invoke functions but if i had to take a tradeoff I think it's a pretty easy one.

It is an issue that yes, like your example, you're often stuck ALSO learning OO because "oh you want to use X library, well that's OO so...", and even then you can isolate your mutable/OO areas really well, but this is more of an issue with it being an second fiddle language. If F# got F# specific libraries for all the C# stuff out there tomorrow I think it'd take off and most people would never look back.

If we're talking basic business logic/beginner programmer stuff, yeah I think F# offers a lot of stuff that makes it flat out easier to use. And if you want to point out complex issues, I feel the biggest one is that something that's intuitively much easier to understand in OO (create a variable/object, populate it on each iteration of a loop depending on logic), can feel daunting as hell in F# (fold).