Go generics are not bad

Re:Go generics are not bad by thegeekpirate on Friday July 08, 2022 @09:25PM (#32030345)

You can instantiate it with [any] then use whatever you'd like https://go.dev/play/p/JeSuB_xYNEf, but I don't think it would work with a type constraint such as `int|string`, which would be a fair point.

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Re:Go generics are not bad by tsimionescu on Saturday July 09, 2022 @01:43AM (#32032155)

Sure, but it's no longer generic, you're just using runtime types again.

This is extremely important, because it means `func (someType[T any]) foo(T x) T`, `x.foo(1)` would return `any`, not `int` like a generic function would.

In fact, if you're going to instantiate a generic type parameter with `any`, I would very much doubt you wanted a generic type in the first place.

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Re:Go generics are not bad by drdaeman on Saturday July 09, 2022 @01:30AM (#32032059)

Oooh. My bad. Thank you! I honestly thought that wasn't possible at all. Today I learned.

However, it won't work for return values, right? Because e.g. `func (some something[T]) hi(b T) T` would return `any` and not whatever it was provided (`int` or `string` respectively).

https://go.dev/play/p/IYoPUQg04sg

Also, I don't think this can work well with types narrower/fancier than `any`, e.g. I had trouble figuring out how to deal with

    type IntOrString interface {
        int | string
    }
    
    type something[T IntOrString] int

https://go.dev/play/p/acwjxdpHTJO

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