Issue: DESTRUCTURING-BIND (Version 2)

[David A. Moon <Moon@STONY-BROOK.SCRC.Symbolics.COM>]

I support version 2 of this.  I have a couple of minor comments:

DESTRUCTURING-BIND should not allow &WHOLE any more than it should allow
&ENVIRONMENT.  Those two features are specific to macroexpanders.

Both LOOP and DESTRUCTURING-BIND allow NIL in place of a variable
name as a way of ignoring a portion of the destructured tree, in
Symbolics current practice.  I think that's a good idea and should
go in the standard.  It's only an abbreviation for a dummy variable
and a DECLARE IGNORE, but the whole destructuring feature is
nothing but an abbreviation anyway.