FP-Go: Functional programming library for Golang

Post by 12345hn6789 » Fri, Aug 18, 2023, 4:35 AM UTC

charlieflowers wrote: post #8

KingOfCoders wrote: post #5

I think map() is useful, even if it does not look like Go and rubs a little against the sprit of simplicity of Go. Wish the for loop in Go would return a result, which could accomplish the same but would be a little bit more Go like x := for y := range z { return y } // unclear return :-( If you want Either, use Haskell. There seems also to be a performance problem with map(). It would work better if Go had Iteration…

`Either` works pretty well in Go. I implemented it and it felt reasonably close to Rust/Haskell (without `try!` of course).

Post by corethree » Fri, Aug 18, 2023, 5:06 AM UTC

12345hn6789 wrote: post #11

charlieflowers wrote: post #8

Earlier quoted context omitted.

`Either` works pretty well in Go. I implemented it and it felt reasonably close to Rust/Haskell (without `try!` of course).

Either is nearly in the language anyways. The vast majority of pragmatic go functions will return [Result, Error] and or just [Error]. We are only missing support to treat this as a monad.

   func compose[A any, B any, C any](a func(A) (B, error), b func(B) (C, error)) func(A) (C, error) {
      return func(aInp A) (C, error) {
        res, err := a(aInp)
        if err == nil {
           return b(res)
        } else {
           return *new(C), err
        }
      }
   }

   func bind[A any, B any, C any](a func(A) (B, error), b func(B) (C, error), aInput A) (C, error) {
      return compose[A, B, C](a, b)(aInput)
   }

Post by kadoban » Fri, Aug 18, 2023, 5:12 AM UTC

zer8k wrote: post #2

I didn't look too much at this but are they offering an alternative to the (IMO ugly) error checking pattern Go enforces? It's interesting to me shoehorning this into Go in particular. Go is notoriously stringent on how you write code.

Post by kadoban » Fri, Aug 18, 2023, 5:13 AM UTC

adamnemecek wrote: post #10

stevefan1999 wrote: post #6

Earlier quoted context omitted.

Just like FPP is incompatible with C, I agree. And if you want a real taste of FPP go with either Haskell, OCaml or even the good ol' LISP

Or Rust.

Post by kerkeslager » Fri, Aug 18, 2023, 5:19 AM UTC

nrabulinski wrote: post #16

keyle wrote: post #12

Potentially a silly question: isn't the garbage collection going to become a problem with this style of Go implementation in large software?

Why would it be a problem? A lot of functional languages are garbage collected and it hasn’t been a problem for them