alt Hacker NewsMy hypothesis is that handles are underused because programming languages make it very easy to dereference a pointer (you just need the pointer) whereas "dereferencing" a handle requires also having the lookup table in hand at the same time, and that little bit of extra friction is too much for most people. It's not that pointers don't require extra machinery to be dereferenced, it's just that that machinery (virtual memory) is managed by the operating system, and so it's invisible in the language.
My current research is about how to make handles just as convenient to use as pointers are, via a form of context: like a souped-up version of context in Odin or Jai if one is familiar with those, or like a souped-up version of coeffects if one has a more academic background.
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Great summary and I think your argument is sound.
I think that it's a generic programming problem: pointers are easier because the type of the pointee is easy to get (a deref) and also its location (memory) but with index-based handles into containers you can no longer say that given a handle `H` (type H = u32) I can use it to get a type `T` and not only that, you've also introduced the notion of "where", that even if for each type `T` there exists a unique handle type `H` you don't know into which container instance does that handle belong. What you need is a unique handle type per container instance. So "Handle of Pool<T>" != "Handle of Pool<T>" unless the Pool is bound to the same variable.
As far as I know no language allows expressing that kind of thing.