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Re: Issue: LOAD-OBJECTS (Version 2)
This looks good. The only thing I have doubts about is:
> The function MAKE-LOAD-FORM-USING-SLOTS can be useful in user-written
> MAKE-LOAD-FORM methods. Its first argument is the object. Its
> optional second argument is a list of the names of the slots to
> preserve; it defaults to all of the local slots.
> MAKE-LOAD-FORM-USING-SLOTS returns forms that construct an equivalent
> object using MAKE-INSTANCE and SETF of SLOT-VALUE for slots with
> values, or SLOT-MAKUNBOUND for slots without values, or using other
> functions of equivalent effect.
Rather than having the second argument default to a list of all instance
slots, it might be better to consider two separate cases:
1. If a second argument is supplied, then MAKE-INSTANCE will be used to
create the object, (using INITIALIZE-INSTANCE to default the slot
values), and then the designated slots will be forced to
have the proper value.
2. Without a second argument, ALLOCATE-INSTANCE will be used to create
the object (without invoking INITIALIZE-INSTANCE or
SHARED-INITIALIZE), and then all the slots will be filled in.
If you are going to specify all of the slot values, then there shouldn't
be a need to compute default values, and it may be undesirable to invoke
INITIALIZE-INSTANCE -- for example, it might complain about missing
required arguments or perform undesired side-effects.
> The default MAKE-LOAD-FORM method for STANDARD-OBJECT signals an
Wouldn't it be permissible to just not have a default method, so that a
"no applicable method" error is signalled?