source: branches/generic-class-file/abcl/README.BRANCH @ 12767

This file describes the goals and current status of the
branch it pertains to. In this case the generic-class-file branch.


Goal(s)
=======

The goal of the branch is to replace the existing class file writer which
is restricted to writing 2 methods in a class file with an extremely
restricted set of signatures.

The new writer will allow any number of methods with no limitation on the
signatures to be used. This allows a number of things impossible today:

 1. Eliminating the external dependency of 'runtime-class.lisp' on ASM
 2. Moving initialization of 'final static' fields to the '<clinit>'
      to make 100% sure they get initialized exactly once
 3. Using the Java-paradigm of having multiple methods with different
      numbers of parameters to fill in default values

--------------- example to go with item (3)
final public LispObject execute() {
  return execute(<default value>);
}

final public LispObject execute(LispObject arg1) {
  return execute(arg1, <default value>);
}

final public LispObject execute(LispObject arg1, LispObject arg2) {
  ...  do actual work ...;
}
--------------- end of example



Design
======




Status
======

The replacement code is located in the java-class-file.lisp file.

TODO:

 * All methods preceded by an exclamation mark have equal names in
   compiler-pass2; this situation is to be resolved eventually.
   Preferrably even before merging back to trunk.

 * Move 'code-bytes' to opcodes.lisp

 * Rename opcodes.lisp to jvm-opcodes.lisp [probably more an action for trunk/]

 * Writing unit-tests

 * Write compiler-pass2.lisp to use WITH-CODE-TO-METHOD to select the
   method to send output to

 * 


The rest of the status is still to be described.