Re: Issue: DESCRIBE-INTERACTIVE (Version 1)

[Kent M Pitman <KMP@STONY-BROOK.SCRC.Symbolics.COM>]

    Date: Mon, 12 Sep 88 20:07 EDT
    From: David A. Moon <Moon@STONY-BROOK.SCRC.Symbolics.COM>

	Date: 12 Sep 88 13:52 PDT
	From: Masinter.pa@Xerox.COM

	I think having DESCRIBE in the standard is much less useful if it is too vague.
	If you want something interactive, use INSPECT.  No?

    In spite of the name of his proposal, I think Kent was proposing to make
    it (slightly) -less- vague. ...

Right. It's already vague. I was proposing to make that vagueness apparent
so it wouldn't be a time bomb in some people's code.

A few more thoughts for what they're worth...

 - CLtL (and Kathy's current draft manual) describes INSPECT as an interactive
   version of DESCRIBE. That doesn't quite contractually oblige DESCRIBE to be
   non-interactive, but it does provide an interesting perspective on intent.

 - Another way to go is to provide an argument saying whether it was ok
   to ask questions:

	DESCRIBE thing &OPTIONAL (query-ok (INTERACTIVE-STREAM-P *STANDARD-OUTPUT*))
	 where QUERY-OK would default according to the interactiveness of the
	 stream in question

   or

	DESCRIBE thing &KEY (verbose :QUERY)
	 where VERBOSE might be one of T, NIL, or :QUERY

 - If people are going to be writing CLOS methods for DESCRIBE, we better get
   started early in saying whether they ought to be incorporating queries into
   their code. [Interestingly, though, the CLOS spec requires the methods for
   DESCRIBE to be compatible with CLtL's description of DESCRIBE, not the
   emerging ANSI spec's description. :-]