Edit System is anti-modularity

[Shepard@MCKENZIE.S&C.Dialnet.Symbolics.COM (Tom Shepard)]

    Date: Tue, 7 May 1991 17:17-0400
    From: Dodds@YUKON.SCRC.Symbolics.COM (Douglas Dodds)

	Date: Tue, 7 May 1991 11:37 EDT
	From: jbarnett@charming.nrtc.northrop.com

	The Edit System command processor command defaults :Include-components to Yes.
	Thus, if I am compulsive and reference the TCP system from my Defsystem, then type
	"Edit system my-system" to a command processor, I get the TCP source slammed into
	edit buffers, one per file.  Is there a flag to surpress this unmodular behavior?
	By the way, I think its nice (though I realy don't care) that it
	includes the juniors
	defined by Defsubsystem.  The problem is that I don't want to see everybody else's
	code, just my system's.

    I don't have a particularly strong defense of that default, but since
    you know what it is, what's wrong with typing "Edit System <system>
    :I C No"?

    I would also comment that making (for example) IP-TCP a component system
    of your own application's system is not the right way to require the
    presence of a generally used system that your system depends on.  The
    right construct for that is to use :REQUIRED-SYSTEMS (:IP-TCP) as an
    option in your DEFSYSTEM.

This is not documented [as of 8.0.1].  How is the behavior of
:REQUIRED-SYSTEMS different from using component systems?

    (See also :LOAD-WHEN-SYSTEMS-LOADED, for optional parts of your system
    that have dependencies on generally used systems that might or might not
    be loaded.)