CLHS: Issue CLASS-OBJECT-SPECIALIZER Writeup

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## Issue CLASS-OBJECT-SPECIALIZER Writeup

    Issue:		CLASS-OBJECT-SPECIALIZER
    References:	Draft 8.81, p.4-15
    		Draft 8.81, Glossary
    		88-002R
    Category:	CHANGE
    Edit history:	Version 1, 28-Mar-91, Kim Barrett
    Status:		Proposal AFFIRM was approved at the 3/91 meeting

    Problem description:

     It was recently noted that the 8.81 draft defines parameter specializer names
     to include class objects.  This inclusion seems to be without basis in
     decisions made by X3J13, and the editor believes it to be an editorial error.

     However, there has been previous discussion of exactly this question on the
     clos mailing list, in which the general consensus seemed to be that class
     objects should be permitted as parameter specializer names.

    Proposal (CLASS-OBJECT-SPECIALIZER:AFFIRM):

     Affirm the wording in the 8.81 draft on page 4-15, which states that a class
     object may be used as a parameter specializer name.

    Examples:

      (defclass foo-class () ())
      (defmethod foo-method ((x #.(find-class foo-class))) x)

    Rationale:

     Not affirming the draft's wording would make parameter specializer names
     inconsistent with other parts of the language, since the use of class objects
     and class names are generally interchangeable when used as type specifiers.

     The draft already says this.

    Current Practice:

     Lucid 4.0 and Chestnut's Lisp to C translator support this.

     Several other implementations probably also support this.

    Cost to Implementors:

     Likely small.

    Cost to Users:

     None.  This is an upwardly compatible change.

    Cost of non-adoption:

     Some applications may already depend on this.  In the mail discussion of this
     question it was mentioned that CLIM may be using class objects as parameter
     specializer names.

    Performance impact:

     None.

    Editorial impact:

     None if accepted, since the draft already contains the necessary words.

    Esthetics:

     Avoiding inconsistancy regarding the distinction between class objects and
     class names when used as type specifiers is more esthetic.

    Discussion:

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