Scala+GWT home


Java source code does not want to be a target language. It has restrictions against logically sound constructs that would be bad Java practice to write by hand. Lex Spoon proposed a plan for an intermediate step, "Loose Java," which we have christened Jribble (pronounced "Dribble").

Jribble is essentially Java with the interfering restrictions removed. Lex: "It's like a puddle of Java. It's also like drivel, which is appropriate enough for a language no one writes and no one reads. Computers can entertain themselves with it well enough."

While far from a spec at this point, the general concepts of Jribble are:

  1. There is no rule in constructors about calling the super() constructor as the syntactically first thing in a constructor.
  2. There is a comma operator expression just like in JavaScript.
  3. Any expression can be used in an expression statement, even useless things like literals.
  4. Types are all Java erased types.
  5. Imports are removed.
  6. Overloading and overriding are as in Java byte code, including override on return type.
  7. Method calls are also as in Java bytecode, and specify the full method signature.

Our efforts so far have been to create a new "jribble" backend to Scala that produces output along these lines, and parallel patches to GWT to understand Jribble input. As we expose more of the issues through this process, we'll formalize Jribble -- as a spec. This hopefully will open some doors to translating other languages into a form that GWT can compile and optimize.

The Jribble concept is interesting as a target language, because it's likely to be an effective target for other JVM languages, not only Scala. Any language that easily produces valid JVM bytecodes, but struggles to produce valid Java, might take advantage of Jribble as a bridge to GWT Javascript compilation.

OK, enough context. Take me home

Fork me on GitHub