Modelessness (Was porting UNIX applications to the mac)

[Barry Margolin]

In article <2637 at cbosgd.ATT.COM> mark at cbosgd.ATT.COM (Mark Horton) writes:
>In article <585 at zeus.UUCP> bobr at zeus.UUCP (Robert Reed) writes:
>>    A useful definition of mode is a state of a user interface that affects
>>    the interpretation of subsequent inputs without obvious indication.
>>
>>The operant words here are "WITHOUT OBVIOUS INDICATION."
...
>>As a novice user of vi, I was constantly surprised by trying to
>>enter text, only to find that I was in command mode (with no obvious
>>indication).  That is the point.
>
>Sorry, Bob, I disagree.  Your version of vi (3.7) doesn't show you when
>you're in input mode, but mine (3.10) does; so does the MS DOS PC/VI
>clone.  (It says "INPUT MODE" right there on the bottom line, or "I"
>if you have terse set.  There are similar messages for r and R modes.)
...
>In spite of this, I still consider vi a moded editor, and I think most
>others do too.  As an extreme example, ex command mode is certainly a
>mode, with a very obvious visual indication (the : prompt and cursor
>at the bottom of the screen.)
>
>There's nothing wrong with being moded,

I think that we need to decide how "obvious" the indications must be
before one is willing to call something "modeless".  I don't consider a
word or two somewhere else on the screen, or a change in shape of the
cursor (as is common in many PC applications) obvious enough.  However,
moving the cursor out of the window, as is done for Emacs ESC-X commands
or Macintosh dialogs, is about as obvious as you can get without
grabbing the user by the collar and screaming "What extended command do
you want?" in his ear.

Emacs and MacWrite, however, are only modeless to a slightly greater
extent than vi.  Emacs has major (C, Lisp, Fundamental) and minor (Auto
Fill, Overwrite, Macro Learn) modes.  MacWrite has modes that specify
the justification, font, and style of the text to be typed in.  I think
that the difference between these and vi is the extent to which use of
the editor depends on the modes; a novice Emacs user might hardly ever
change modes, but a vi can't be used without going between insert,
overwrite, and edit modes relatively frequently.
-- 
    Barry Margolin
    ARPA: barmar at MIT-Multics
    UUCP: ..!genrad!mit-eddie!barmar