This implementation works by detecting assignments
to constant properties in elaboration. Allow initializer
assignments to assign to the constant, error all other
assignments, and otherwise treat the constant like any
other property.
Emit the elaborated class methods. Also generate root scopes to
represent the classes in order to hold the methods. These scopes
can also in the future be used to implement static properties.
This provides the ivl_target.h interface for class definitions
and expressions, the vvp code generator support for class objects
and properties, and the vvp run time support. Trivial class objects
now seem to work.
Add properties to the classes, and elaborate expressions that
have class properties. Describe class object property references
all the way down to the stub target.
Stephen Williams