What version of Go are you using (go version)?

$ go version
go version devel go1.18-e17439e087 Sat Aug 21 00:55:22 2021 +0000 darwin/arm64

Does this issue reproduce with the latest release?

Yes

What did you do?

package main

import "fmt"

type Option[T any] func(*Parser[T])

func Upgrade[T any]() Option[T] {
	return func(*Parser[T]) {}
}

func Description[T any](string) Option[T] {
	return func(*Parser[T]) {}
}

type Parser[T any] struct {}

func New[T any](options...Option[T]) *Parser[T] {
	p := &Parser[T]{}
	for _, o := range options {
		o(p)
	}
	return p
}

type SomeThing struct {}

func main() {
	p := New[SomeThing](Upgrade(), Description("A description"))
	// p := New[SomeThing](Upgrade[SomeThing](), Description[SomeThing]("A description"))
	fmt.Println("???", p)
}

This program fails with the following:

./main.go:24:29: cannot infer T (/Users/aat/Projects/goroot/foo/main.go:7:14) ([<nil>])

Which makes sense given the scope of type inference in the design. However, I thought I'd file this issue anyway, as functional options are very common in Go and this will make them quite tedious to use in conjunction with generic types:

	p := New[SomeThing](Upgrade[SomeThing](), Description[SomeThing]("A description"))

The issue is phrased as a question in case there is some solution I'm not aware of, or it's just plain out of scope.

PS. Thanks for all the hard work getting it to this stage, it's looking super promising :)