Interpreting Go

Interpreting Go is a good idea. In fact, a JIT for Go would be a very interesting idea as well. In a language that makes heavy use of virtual dispatch like Go does (via interfaces), you can often get a lot of mileage out of speculative devirtualization. With a JIT you can easily observe the concrete types that flow through each call site, allowing for optimizations you can't easily do with AOT compilation (without PGO, anyway). You can even do aggressive optimizations like observing that only one type that's currently loaded in the program conforms to an interface and devirtualize accordingly, knowing that you can undo that optimization if more code gets loaded later on that invalidates this assumption.

I would like to call interpreted Go code from compiled Go code, say, like: run("dynamic.goi"). Would I be able to call back into the compiled code from the interpreted code? Can the two parts share variable state?

Could you use this to make a Go REPL?