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Re: Issue DEFCONSTANT-NOT-WIRED
- To: Eric Benson <eb@LUCID.COM>
- Subject: Re: Issue DEFCONSTANT-NOT-WIRED
- From: Brad Miller <miller@CS.ROCHESTER.EDU>
- Date: Fri, 7 Oct 88 17:41 EDT
- Cc: Gray@DSG.csc.ti.com, sandra%defun@CS.UTAH.EDU, CL-Compiler@SAIL.STANFORD.EDU
- In-reply-to: <8810071952.AA00510@blacksox>
- Organization: University of Rochester, Department of Computer Science
- Phone: 716-275-1118
- Postal-address: 610 CS Building, Comp Sci Dept., U. Rochester, Rochester NY 14627
- Reply-to: miller@CS.ROCHESTER.EDU
- Sender: miller@CS.ROCHESTER.EDU
Date: Fri, 7 Oct 88 12:52:34 pdt
From: Eric Benson <email@example.com>
I disagree. You may not remember, but DEFPARAMETER was defined to be
equivalent to Zetalisp's DEFCONST. DEFCONST was always used to denote
values that would "never" change, even though the compiler was not
licensed to substitute their values. After the Common Lisp version of
DEFCONSTANT was accepted, DEFPARAMETER was proposed to be used in
place of DEFCONST in cases where DEFCONSTANT isn't desirable. As it
turns out, most uses of DEFCONST have been converted to DEFCONSTANT,
so DEFPARAMETER has been a bit neglected.
I use DEFCONSTANT for symbols whose definitions will never change (or at
least, I am willing to recompile all references, as if I change a macro) but
DEFPARAMETER for cases where the definitions will not change *over a
particular execution of the program* but may change *between executions of
the program* and thus the compiler must treat it as a variable, so I don't
have to recompile references.
Have I missed something? Am I misusing DEFPARAMETER?
Brad Miller U. Rochester Comp Sci Dept.