Why can't you do this in Go? I'm 99% sure we can allocate a massive array of bytes using safe Go and use unsafe to cast a chunk of bytes to an instance of a type. This isn't type safe, but neither would the equivalent C code.
You are misunderstanding the thread, I just mentioned some of the languages I like (still waiting for Go's generics), and the comment I was replying to made an assert about an implementation that uses cgo.
Both of us are dismissing the assertion that "Arenas are, however, unfeasible to implement in Go because it is a garbage collected language."
You can do manually memory allocation via a syscall into the host OS, use unsafe to cast memory blocks to the types that you want and then clean it all up with defer, assuming the arena is only usable inside a lexical region, otherwise extra care is needed to avoid leaks.
I was proposing the cgo option because it's already implemented.
I _think_ allocating a slice of contiguous bytes and using unsafe pointers should work fine as long as you are very cautious about structs/vars with pointers into the buffer getting freed by the GC.
> I _think_ allocating a slice of contiguous bytes and using unsafe pointers should work fine as long as you are very cautious about structs/vars with pointers into the buffer getting freed by the GC
Go's GC is conservative, so I don't think you need to take any special caution in that regard. I would expect that you just need to take care that your casts are correct (e.g., that you aren't casting overlapping regions of memory as distinct objects).
