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Re:  &rest replacement/addition
- To: Sean.Engelson@spice.cs.cmu.edu, barmar@Think.COM
 
- Subject: Re:  &rest replacement/addition
 
- From: rst@Think.COM
 
- Date: Mon, 4 Apr 88 12:29:50 edt
 
- Cc: common-lisp@sail.stanford.edu, spe@spice.cs.cmu.edu
 
   From: Barry Margolin <barmar@Think.COM>
   Subject: &rest replacement/addition
   Actually, if this were added, the operations that extract the arguments
   need not be special forms.  &MORE-ARGS <var> could bind <var> to an
   object of type MORE-ARGS.  Common Lisp would only specify accessors for
   this object, so it could be passed along with no possibility of strange
   side-effects.  APPLY could also be extended to allow a MORE-ARGS in
   place of a list as its last argument.
                                                barmar
But can an object of type MORE-ARGS be returned from a function, or
otherwise stuffed in data structures which survive the dynamic extent
of the function call that spawned them?  That's what this whole
argument started with...
(Sean's original proposal had no &more-args variables.  Any
implementation would, of necessity, have some such thing internally,
but users would not be able to get their hands on them).
rst