You don't need support. Monad composition isn't a special feature it can be implemented directly.
Not an expert in Go but I think you can do this:
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
}
}
}
The above is equivalent to haskells fish operator >=>
The bind operator (>>=) can be implimented in terms of composition:
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)
}
