Deconstructing and reconstructing structures

Hi,

I'm looking for a way to automatically save and load structures.
(Yes, I know about the problems with equality and cloning and
that it's very difficult to do this in a completely general way.)

As far as I know, there's no portable way to find out the 'slot
names', 'slot values' and type of a structure. I didn't find
any documentation about a Lispworks-specific way either.
So I've done some APROPOSing. (I found a typo while doing that,
by the way. You might want to fix the names of the functions
STRUCTURE::UNKNWON-STRUCTURE-SET-SLOT-VALUE and
STRUCTURE::UNKNWON-STRUCTURE-SLOT-VALUE, if you didn't fix them
already in version 4.3.)

I've included some documentation below on what I found out about
'generic' structure functions. I have three questions about this:
 1. Could you tell me if this documentation is correct?
 2. Can I rely on these functions to continue to work in future
    versions of Lispworks?
 3. Is there some function like MAKE-STRUCTURE that can construct
    a structure from a list of slot-names and a list of slot-values
    without having to cons up a plist?

Thanks a lot,

Arthur Lemmens

 --

The following functions are available (i.e. exported) in the STRUCTURE
package:

- STRUCTURE-NAMES-AND-VALUES struct
  Returns two values: a list with the names of the structure slots, and
  a list with the corresponding values. The slot names are not keywords,
  but 'normal' symbols (from the package in which the DEFSTRUCT-form was
  evaluated, I suppose).
  Example: (STRUCTURE-NAMES-AND-VALUES #S(TEST FOO 1 BAR 2))
           -> (FOO BAR)
              (1 2)

- MAKE-STRUCTURE type &rest args
  Creates a new structure of the given structure-type.
  ARGS is just like the arguments for the structure constructor function.
  Example: (MAKE-STRUCTURE 'TEST :FOO 1 :BAR 2) -> #S(TEST FOO 1 BAR 2)

- STRUCTURE-CLASS-SLOT-NAMES structure-class
  Returns a list with the slot names of the structure-class.
  Example: (STRUCTURE-CLASS-SLOT-NAMES (CLASS-OF #S(TEST FOO 1 BAR 2)))
           -> (FOO BAR)

- STRUCTURE-TYPE struct
  Returns the 'type' of the struct.
  Example: (STRUCTURE-TYPE #S(TEST FOO 1 BAR 2)) -> TEST

- STRUCTURE-SLOT-DETAILS structure-class structure-slot-name
  Returns four values:
  1. ???
  2. The type of the slot.
  3. The name of the reader function for the slot.
  4. The (unevaluated) initform for the slot.