I'm not really a programming language expert, but it seems to me that having an implementation being the spec wouldn't be a good idea. If the Streem implementation has a bug, then the bug becomes the authoritative behavior. Any platform specific quirks would also make it difficult to have defined behavior.
Implementations are nearly always the spec when a language is young. You want to be able to experiment and make changes. Then as it matures, you typically get a spec.
Sure, but this is not finished at all. Starting with the spec instead of a prototype implementation sounds like a very very limiting and unrewarding design process.
There's an old argument about worse is better. The gist is, doing things the right way is hard and takes a long time. sometimes, it's better to just get something simple out there and deal with the problems later.
Right now, the closest thing to a spec is the sample FizzBuzz code (as an implicit spec that "this code will solve FizzBuzz"); there is no implementation (just work-in-progress parser/lexer code.)
So, while I'll agree that there are issues that come from the implementation being the spec of a language in general, I would say we are well earlier than the point at which we can identify that as a problem with Streem.
Welcome to PHP. The Zend Engine 2 is basically the spec, even though Facebook has recently (couple of weeks ago) started writing a spec to make sure their HHVM is compatible.
