use Perl

What is CLU?

• An early sorta-OO language. It appeared in the late 70s, and was used as a teaching langauge in the early and mid 80s. It has "clusters", which are a set of operations that can be performed on an opaque data abstraction. (Like a class, but no inheritance, and slightly awkward syntax.)
• A language with some interesting features. Parameterized types; parameterized procedures; iterators; parameterized iterators; exceptions.
• It's a language I learned to program in once, so therefore it can never be allowed to die.

Why port to Parrot?

• Clusters and exceptions will test bits of Parrot not heavily stressed yet.
• While CLU iterators don't have to be implemented with coroutines, they can be. So that gets tested too.
• It's strongly-typed, and Parrot should have at least one B&D language.
• I wanna.
• I never bothered taking the compiler course, so this is my chance to use the Dragon book in anger.
• I get to play with Parse::RecDescent and Parrot.

Things I have:

• A Perl6 grammar that looks like it might parse CLU. Useless until Perl6::Rules gets released.
• A Parse::RecDescent grammar that parses the bits of CLU I've fed into it so far.
• The outline of the parsetree cleanup code.
• Vague ideas of how I'm going to do code emission. (I'm going to target IMCC.)

Things I need:

• A set of parsing tests.
• Finish the AST cleanup code.
• Write the code generation.
  • Do I understand the current state of the calling conventions?
  • How is linking supposed to happen?
  • How out-of-date is Perl 6 Essentials already?
• Implement the builtin types and the standard library (or at least enough of streams to print).
• Tests, tests, tests