* Ordering

	Can a constant_expression invoke overloaded operators?
	Explicit user-defined conversions?

* Visibility

	I am not reporting errors on visibility yet.

* Error handling

	Normalize, and use Tokenizer location 

* Enumerations

	Currently I am not resolving enumerations.

	Either I track them with `RecordEnum' as I do with classes,
	structs and interfaces or I rewrite the code to visit type
	containers and `walk' the enums with this process. 

* Known problems:

  Cast expressions

	They should should use:

		OPEN_PARENS type CLOSE_PARENS

	instead of the current production which is wrong, because it
	only handles a few cases.

	Complex casts like:

		Array r = (string []) object

	Wont be parsed.
  
* Interfaces

	For indexers, the output of ix2.cs is different from our
	compiler and theirs.  They use a DefaultMemberAttribute, which
	I have yet to figure out:

	.class interface private abstract auto ansi INTERFACE
	{
		.custom instance void [mscorlib]System.Reflection.DefaultMemberAttribute::.ctor(string) 
		= ( 01 00 04 49 74 65 6D 00 00 )                      // ...Item..
		...
	}

* Interface indexers

	I have not figured out why the Microsoft version puts an
	`instance' attribute, and I am not generating this `instance' attribute.

* Constructors

	Currently it calls the parent constructor before initializing fields.
	It should do it the other way around.

* Use of EmitBranchable

	Currently I use brfalse/brtrue in the code for statements, instead of
	using the EmitBranchable function that lives in Binary

* Create an UnimplementedExpcetion

  	And use that instead of plain Exceptions.

* Bug

	Currently I cant cope with a = b = 1;
	Because the stack is empty after b = 1

	The current mechanism uses the return value of Emit to figure if there
	is something in the stack after we return. 

	But MAYBE we need to pass an extra argument: `Do I expect
	something in the stack' to Emit, that way we can optimize whether
	it is worth duping stuff on the stack or not.

	And we can also make sure that we dont generate extra pops.

