[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
issue SHARP-COMMA-CONFUSION, version 1
- To: firstname.lastname@example.org
- Subject: issue SHARP-COMMA-CONFUSION, version 1
- From: Kent M Pitman <KMP@STONY-BROOK.SCRC.Symbolics.COM>
- Date: Fri, 23 Dec 88 15:43 EST
- Cc: email@example.com
- In-reply-to: <8810171903.AA22260@defun.utah.edu>
I approve of the ideas being discussed, but ONLY contingent on
LOAD-TIME-VALUE being introduced.
I don't think the current practice assesses things correctly.
#, is not used very frequently.
Although #, is used infrequently in typical user code, the functionality
it provides is very important to some advanced applications. Maintainers
of such applications have generally expressed a willingness to give up #,
only if a suitable alternative is offered (see issue LOAD-TIME-EVAL).
CLOS and language translators are examples of pieces of code which have
been cited by people who say they could not be implemented efficiently in
Lisp without a facility such as this.
In Cost To Users, the DEFPARAMETER technique described has been demonstrated
to be unacceptable for the general problem. The importance of LOAD-TIME-EVAL
needs to be promoted here as well.
I am optimistic that LOAD-TIME-EVAL will pass, and so I don't think this
will keep #, from passing, but:
- I want people who vote for this to realize the importance of voting
- On the off chance LOAD-TIME-EVAL doesn't pass, I want people to have
been warned that the consequences were severe for some major applications.
- I want the records to reflect the actual rationale people should and
hopefully will be using to make these decisions.
In particular, the issue of LOAD-TIME-EVAL goes beyond "thinking of a
variable name". A bunch of other issues which were raised in mail are
left out here:
- There is no way for an expression from inside a program for a macro
to `emit' a top-level definition.
- Variables are high overhead (typically at least five pointer-size
units per symbol), and so zillions of independent names would bloat
- Variables are typically slower than immediate quantities can be.