I am assuming that by "made up" language, you mean a language that you have defined and created.
Any code posted in that language prior to you completing the interpreter for it would by definition be hypothetical code. There's no way for anyone to verify that the code works as intended, because well... it doesn't work at all. There's nothing to run that code.
However, that's not what you asked. You asked if you could have your interpreter reviewed.
I see no reason why you couldn't. It would probably take a good bit of effort to explain the grammar behind your language, and it would probably be a good idea to break the code down into several reviews of manageable chunks, but why not?
Let's run down the magic listmagic list.
- Is code included directly in my question? (See Make sure you include your code in your question below.)
Let's assume so.
- Am I an owner or maintainer of the code?
Yup.
- Is it actual code from a project rather than pseudo-code or example code?
Sure is.
- Do I want the code to be good code? (i.e. not code-golfing, obfuscation, or similar)
You wouldn't be here if you didn't.
- To the best of my knowledge, does the code work as intended?
Does it? I'm assuming yes for the purpose of the meta.
- Do I want feedback about any or all facets of the code?
Again, I don't think you'd be here if you didn't.