Cannot instantiate T(ype) passed as pointer T?

[Slawomir Pryczek]

https://gotipplay.golang.org/p/ojY3RRJRJgy

func GenericData[T DATA, T1 any]() {

}

When DATA is interface of pointer type, so methods can modify the underlying structure...

// T1 <- any type, so can instantiate but can't increment as there's no interface

var tt T1 
fmt.Println(tt)

var d T      // T <- DATA interface type, so can't initialize but can instantiate

can't instantiate because the object will never initialize (nil)

Can i create new object of type DATA somehow?

[Slawomir Pryczek]

Actually this is better code for the question

https://gotipplay.golang.org/p/GQlB2tyyj53

[Axel Wagner]

I'm not *entirely* sure what you are asking, but does this help, perchance?

https://gotipplay.golang.org/p/DmxDIdHrV8o

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[Slawomir Pryczek]

Thanks, actually that's what I was looking for.  Don't have much experience using generics (like 2 days) but looks rather inconvinient to do that. This pattern is convinient for you and you're using it in your code? You think there are plans to introducing some feature which will allow to work with *interfaces & generics "normally" (without additional boilerplate?)

[Axel Wagner]

The design doc says this:

What we need is a way to say that the type constraint applies to either the pointer method set or the value method set. The body of the function would be required to only call the method on addressable values of the type.

It's not clear how often this problem comes up in practice.

 

So, it's on the radar, but it's not clear if this will happen - and if so, when.

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