CLHS: Function MAKE-LOAD-FORM-SAVING-SLOTS

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Function MAKE-LOAD-FORM-SAVING-SLOTS

Syntax:

make-load-form-saving-slots object `&key` slot-names environment

=> creation-form, initialization-form

Arguments and Values:

object---an object.

slot-names---a list.

environment---an environment object.

creation-form---a form.

initialization-form---a form.

Description:

Returns forms that, when evaluated, will construct an object equivalent to object, without executing initialization forms. The slots in the new object that correspond to initialized slots in object are initialized using the values from object. Uninitialized slots in object are not initialized in the new object. make-load-form-saving-slots works for any instance of standard-object or structure-object.

Slot-names is a list of the names of the slots to preserve. If slot-names is not supplied, its value is all of the local slots.

make-load-form-saving-slots returns two values, thus it can deal with circular structures. Whether the result is useful in an application depends on whether the object's type and slot contents fully capture the application's idea of the object's state.

Environment is the environment in which the forms will be processed.

Examples: None.

Side Effects: None.

Affected By: None.

Exceptional Situations: None.

See Also:

make-load-form, make-instance, setf, slot-value, slot-makunbound

Notes:

make-load-form-saving-slots can be useful in user-written make-load-form methods.

When the object is an instance of standard-object, make-load-form-saving-slots could return a creation form that calls allocate-instance and an initialization form that contains calls to setf of slot-value and slot-makunbound, though other functions of similar effect might actually be used.

The following X3J13 cleanup issues, not part of the specification, apply to this section:

- MAKE-LOAD-FORM-SAVING-SLOTS:NO-INITFORMS
- LOAD-OBJECTS:MAKE-LOAD-FORM
- MAKE-LOAD-FORM-CONFUSION:REWRITE

Copyright 1996-2001, Xanalys Inc. All rights reserved.