What's wrong with the way that Java, C# a, and C++ handle generics? I see this complaint fairly regularly, but I was never sure why. Is it how the compiler handles it, or how the language defines it that is the reason for this dislike? Genuine curiosity.
This is the lazy answer I know, but I wanted to at least answer your genuine curiosity: There is ample research available online on the subject that explains it in depth and far better than I ever could. However, I will leave you with a few quotes that help at least paint the picture.
From the Golang FAQ:
> Generics are convenient but they come at a cost in complexity in the type system and run-time. We haven’t yet found a design that gives value proportionate to the complexity
Quote from Russ Cox:
> The generic dilemma is this: do you want slow programmers, slow compilers and bloated binaries, or slow execution times?
Finally, one of the reasons the C++ or Java approach has never been palatable to Go core devs is summarized from this Rob Pike quote from his famous "Less is Exponentially More" blog post:
> If C++ and Java are about type hierarchies and the taxonomy of types, Go is about composition
So therefore it really is also a matter of finding a generics approach that lives up to that spirit as well. Contracts I think are approaching that.
All that said, user defined generics (since technically speaking, Go has many generic capabilities today already) are coming to Go, they just aren't being rushed. I think we will be happy with the generics implementation in Go within the next year.
