I was just reading a bit about the HQ9+ programming language ( http://esolangs.org/wiki/HQ9 , http://en.wikipedia.org/wiki/HQ9%2B and http://www.cliff.biffle.org/esoterica/hq9plus.html ), and it tells me something about a so called 'accumulator' which can be incremented, but not be accessed. Also, using the + doesn't manipulate the result:
H+H
Hello World
Hello World
Can anyone explain me how this works, what this does and if it even makes any sense? Thanks
Having written an implementation, I think I can say without a doubt that it makes no sense at all. I advise you to not worry about it; it's a very silly language after all.
It increments something not accessible, not spec-defined, and apparently not really even used. I'd say you can implement it however you want or possibly not at all.
It's a joke.
There's also an object-oriented extension of HQ9+, called HQ9++. It has a new command ++ which instantiates an object, and, for reasons of backwards-compatibility, also increments the accumulator register twice. And again, since there is no way to store, retrieve, access, manipulate, print or otherwise affect an object, it's completely useless.
What everyone else said is correct, and I would just like to add: It's just a silly nothing; you can call any incremented variable an "accumulator" because that is its function.