mode-line major and minor mode help text and bindings

mode-line major and minor mode help text and bindings

[Drew Adams]

emacs -Q

C-x d <some directory>
M-x outline-minor-mode  ; or any other minor mode

Help echo (tool tip) in mode line, with pointer over lighter "Outl":
"mouse-2: help for minor modes, mouse-3: minor mode menu". However, with
pointer over a major mode name, such as "Dired by name", is this: "mouse-1:
major-mode-menu, mouse-2: help for current major mode".

There is a lack of symmetry here, and a few sources of confusion.

1. "major-mode-menu": This should be "major-mode menu" (or "major mode
menu", depending on the hyphenation convention used by Emacs).

2. "minor mode menu": This looks just like the major-mode case, but in this
case it is not a menu for the indicated minor mode but a menu to turn on/off
*any* minor modes. This should be called something like "menu to change
minor modes" or "menu of minor modes".

3. Why is the menu for the major mode on mouse-1 and the menu for the minor
modes on mouse-3? Why not put them both on mouse-3 (but see #6, below, for a
better suggestion).

4. "help for minor modes" (with an `s') is apparently not correct. The
mouse-3 minor-modes menu shows that these minor modes are all turned on:
font lock, line number, and outline. However, mouse-2 over the minor-mode
lighter gives only the help for outline-minor-mode (perhaps since that is
the only lighter?); it does not give "help for [all] minor modes". If only
one mode is described then this should be called "help for this minor mode".

5. Enhancement suggestion: Have mouse-1 toggle the minor mode (of that
lighter). This is a shortcut for using the minor-modes menu and choosing the
corresponding menu item.

6. Enhancement suggestion: It seems a bit silly to have the same menu be on
each of the minor-mode lighters - a waste of the mouse-3 binding.
Suggestion: Instead, add this minor-modes menu to the major-mode menu as a
submenu, "Choose Minor Modes". Bonus: if the minor mode (for that lighter)
has, itself, a menu, that could be on mouse-3.

7. Unrelated question: Why do we call the mode-line name of the mode a
"lighter" (and use the keyword ":lighter" for `define-minor-mode')? Where
does this term come from - is it perhaps a translation? Why don't we call it
the "mode-line name" of the mode (and use keyword :mode-line-name)? Who will
understand "lighter" for this without an explanation? Who will look for that
term in the Emacs Lisp-manual index? (BTW - Foldoc has no definition for
"lighter", so I suspect it is not a previously used computing term:
http://foldoc.org/foldoc.cgi?query=lighter&action=Search.)

RE: mode-line major and minor mode help text and bindings

[Drew Adams]

Another item:

8. Some minor modes, even with a lighter and even if they can be toggled, do
not appear in the menu of minor modes. Why? What are the criteria that
determine this? For example, View (minor) mode in a *Help* buffer - it is
not in the menu, but you can toggle it via `M-x view-mode'.

Re: mode-line major and minor mode help text and bindings

[Richard Stallman]

    1. "major-mode-menu": This should be "major-mode menu" (or "major mode
    menu", depending on the hyphenation convention used by Emacs).

    2. "minor mode menu": This looks just like the major-mode case, but in this
    case it is not a menu for the indicated minor mode but a menu to turn on/off
    *any* minor modes. This should be called something like "menu to change
    minor modes" or "menu of minor modes".

    3. Why is the menu for the major mode on mouse-1 and the menu for the minor
    modes on mouse-3? Why not put them both on mouse-3 (but see #6, below, for a
    better suggestion).

Mouse-3 does minor modes in both places.  This is necessary so that
there is a way to turn on minor modes even when none are on.

    4. "help for minor modes" (with an `s') is apparently not correct. The
    mouse-3 minor-modes menu shows that these minor modes are all turned on:
    font lock, line number, and outline. However, mouse-2 over the minor-mode
    lighter gives only the help for outline-minor-mode (perhaps since that is
    the only lighter?); it does not give "help for [all] minor modes". If only
    one mode is described then this should be called "help for this minor mode".

I took action on these four.  Thanks.

    5. Enhancement suggestion: Have mouse-1 toggle the minor mode (of that
    lighter). This is a shortcut for using the minor-modes menu and choosing the
    corresponding menu item.

That would only give you a way to turn minor modes off.
I don't think it is a good idea.

    6. Enhancement suggestion: It seems a bit silly to have the same menu be on
    each of the minor-mode lighters - a waste of the mouse-3 binding.
    Suggestion: Instead, add this minor-modes menu to the major-mode menu as a
    submenu, "Choose Minor Modes". Bonus: if the minor mode (for that lighter)
    has, itself, a menu, that could be on mouse-3.

That would be less convenient, and there is nothing else natural
for mouse-3 to do here.

mouse-1 on minor-mode lighter in mode line could bring up the minor mode's menu

[Drew Adams]

For consideration after the release:

Mouse-1 on a minor-mode lighter in the mode line does nothing special - it
just runs `mouse-drag-mode-line'. When a minor mode has its own menu, why
not display that for mouse-1, just as we do for major modes?

---

[Note: This is a different suggestion from what was discussed in thread
"mode-line major and minor mode help text and bindings" of 2006-04-29. The
part of that discussion that concerned minor-mode menus was about mouse-3:

> From: Richard Stallman
> Sent: Saturday, April 29, 2006 8:04 PM
>
>     6. Enhancement suggestion: It seems a bit silly to have the
>        same menu be on each of the minor-mode lighters - a waste
>        of the mouse-3 binding. Suggestion: Instead, add this
>        minor-modes menu to the major-mode menu as a submenu,
>        "Choose Minor Modes". Bonus: if the minor mode (for
>        that lighter) has, itself, a menu, that could be on mouse-3.
>
> That would be less convenient, and there is nothing else natural
> for mouse-3 to do here.
]

Re: mouse-1 on minor-mode lighter in mode line could bring up the minor mode's menu

[Richard Stallman]

    Mouse-1 on a minor-mode lighter in the mode line does nothing special - it
    just runs `mouse-drag-mode-line'. When a minor mode has its own menu

What does that mean -- for a minor mode to "have its own menu"?

RE: mouse-1 on minor-mode lighter in mode line could bring up the minormode's menu

[Drew Adams]

> From: Richard Stallman
>     Mouse-1 on a minor-mode lighter in the mode line does nothing
>     special - it just runs `mouse-drag-mode-line'. When a minor
>     mode has its own menu
>
> What does that mean -- for a minor mode to "have its own menu"?

For example:

(let ((map (make-sparse-keymap "Foo")))
  (define-key foo-mode-map [menu-bar] (make-sparse-keymap))
  (define-key foo-mode-map [menu-bar foo] (cons "Foo" map))
  (define-key map [foo1] '("Foo 1" . foo1))
  ...)

When minor mode foo is enabled (not shown), menu Foo would be added to the
menu-bar. Menu Foo could also be used as a popup on the Foo lighter in the
mode-line. This would provide the same behavior we have now for major modes
(e.g. Info).

Re: mouse-1 on minor-mode lighter in mode line could bring up the minormode's menu

[Richard Stallman]

Now I understand -- you mean that the minor mode has its own menu bar
item.

However, the feature you suggested doesn't seem very useful to me.

RE: mouse-1 on minor-mode lighter in mode line could bring up theminormode's menu

[Drew Adams]

> Now I understand -- you mean that the minor mode has its own menu bar
> item. 

Yes.

> However, the feature you suggested doesn't seem very useful to me.

It's your call, but why would it be less useful than the same (existing)
feature for major modes?

(There is nothing necessarily minor about a minor mode, BTW.)

Re: mouse-1 on minor-mode lighter in mode line could bring up theminormode's menu

[Richard Stallman]

    It's your call, but why would it be less useful than the same (existing)
    feature for major modes?

What feature is that?

RE: mouse-1 on minor-mode lighter in mode line could bring uptheminormode's menu

[Drew Adams]

>     It's your call, but why would it be less useful than the same
>     (existing) feature for major modes?
>
> What feature is that?

Putting the major-mode menu-bar menu on the major-mode mode-line indicator.
For example, click Info in the mode line, and you get the Info-Mode menu-bar
menu.

My idea was to simply do the same thing for minor-modes. When they have
menu-bar menus, they are likely to be as important as a major-mode menu-bar
menu.

Re: mouse-1 on minor-mode lighter in mode line could bring uptheminormode's menu

[Richard Stallman]

Now I understand what you're suggesting.  Since mouse-1 has no current
meaning on the minor mode indicators, it would be harmless to add
this meaning, and it would be consistent.

So it is ok with me, if someone wants to do it.

Sorry I misunderstood at first.