My quest to understand What Programming Languages Are Made Of has led to me start reading the Beta Programming Language book. I've only gotten as far as Chapter 3 so far, but I've already seen enough quirks in the language to have repaid the time.
If I see the implications properly, it looks as if Beta unifies method calls and object construction. That is, the language has no functions or methods per se; rather, all code lives in what would Java or Scala would consider constructors or instance initialization. Instance variables play the role of local variables.
It's easy to observe that stack frames are like objects, in that both are usually laid out as structs accompanied (in languages with managed memory) by a pointer to some sort of descriptor. But it's a bold leap to say that stack frames are objects.
I haven't read far enough to be sure that my understanding is correct. It would also be interesting to see whether Beta has any notion of alternate constructors—which, when viewing Beta objects as functions, would have an effect something like default function arguments.
Is the Beta approach part of the answer to the puzzle of What Are Constructors Made Of? I haven't figured that out yet.
I've seen Beta mentioned a few times, but never heard of anyone using for it anything. I wonder whether it failed to gain traction because people always assumed it was still in beta.