struct variable `p' removal checked in

[Ben Pfaff]

I just checked in a big set of changes that gets rid of struct
variable's `p' and `get' members, as we discussed earlier on the
list.  Doing it properly seemed to require cleaning up and
reworking a fair amount of seemingly unrelated code.  Since this
code was in pretty fair need of it I did so anyway.

It passes `make distcheck' but due to the amount of code upheaval
there were probably bugs introduced by this, especially data
file, system file, and portable file reading and writing.  Let me
know what you find and I'll fix it.

Check-in message follows.  See ChangeLog for more detail.

    Instead of making system or portable file readers responsible for
    dropping and reordering variables, make them read full cases and
    let the caller take care of any changes.

    Instead of providing a system or portable file writer with a raw
    case in the format needed for output, provide it with a regular
    case.  The writer takes care of any needed translation.

    Instead of treating `struct file_handle' as a class to subclass
    into data files, system files, and portable files, instead use it
    as a helper that coordinates access.  Now it is opaque, too.

    Break dictionary functions into separate header file.

    Get rid of procedure-specific union in struct variable, using
    instead a void * pointer and a destructor function.

-- 
Ben Pfaff 
email: address@hidden
web: http://benpfaff.org