I'm using a DSL to return a closure expression and it's accepting it (after some minor modifications to the compiler pod) but now it gets me to this wonderful looking error:

sys::Err: java.lang.VerifyError: (class: fan/couroutine_test/co1, method: doCall signature: ()V) Falling off the end of the code

I created a gist with my changes to the compiler and my code to output the closure.

https://gist.github.com/1959419

The source I'm using to test is currently:

Void test1() {
  x := Coroutine<| echo("This is a test!"); return |>
  x()
}

Clearly there's still some processing to be done on this closure, maybe I need to add a return statement or something special like that?

Closures are by far the most complicated aspect of the compiler and have to be run through many steps.

It would be a lot simpler if you could have the closure be an argument to your Dsl. Do you think you could do this:

Void test1() {
  x := Coroutine<||> {  echo("This is a test!"); return  }
  x()
}

We can always clean-up syntax, but then the closure would just be a normal closure processed by compiler. Your Coroutine would have to evaluate to something that took an it-block as an argument.

Hi brian,

Unfortunately I want to transform the closure into a state machine of some sort, I'm not using it verbatim. I don't think having it passed as a parameter would make it feasible to do that.

Actually I seem to have the closure part working now, I just needed to call the Normalize phase on the closure and make sure it was added to compiler.closures

I updated the gist with the new version, in case anyone is curious.

Now onto the hard part of transforming the closure into a state machine of some sort!