Go generics draft design: building a hashtable

Re:Go generics draft design: building a hashtable by lsllc on Wednesday June 17, 2020 @10:54PM (#23559340)

Ah, right, I missed this:

https://go.googlesource.com/proposal/+/refs/heads/master/des...

Hmmm ... not sure how I feel about that. Ok so my original example becomes this:

  func (obj *SomeType) Foo(type K, V, Q comparable)(key K, val V) (*OtherType(Q, V), error) {
      ...
  }

Which is only slightly better [without the generic type].

Don't get me wrong, I'm a big fan of Go, but I'm kind of on the fence about generic types. I've made do with casting interfaces and type-casts for many years and I'm OK with it (honestly, glad to not be a C++ or Java programmer anymore).

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Re:Go generics draft design: building a hashtable by mseepgood on Thursday June 18, 2020 @01:07AM (#23559961)

> Ok so my original example becomes this

No, you still don't understand. Methods can't have additional type parameters, only functions. This part is not allowed in your "example":

    (type K, V, Q comparable)

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Re:Go generics draft design: building a hashtable by lsllc on Thursday June 18, 2020 @12:34PM (#23564793)

The doc says:

> Generic types can have methods. The receiver type of a method must declare the same number of type parameters as are declared in the receiver type's definition. They are declared without the type keyword or any constraint.

So my original example should have been:

  func (obj *SomeType(K, V)) Foo(key K, val V) (*OtherType(K, V), error) {
        ...
  }

(hopefully this is now correct!).

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