Highlighting the right margin

Highlighting the right margin

[fortepianissimo]

I've been trying to make an .el file I downloaded to work so I can see
where the right margin starts to avoid coding long lines.

The file is highlight-beyond-fill-column.el, and I have this line in my
.emacs

(require 'highlight-beyond-fill-column)


But after restarting emacs (22.0.50 on Mac OS X), hitting M-X and then
trying to invoke the function highlight-beyond-fill-column, I couldn't
find the function at all.

I'm almost completely ignorant on elisp - could someone show me some
voodoo magic that I need to put into my .emacs file to make this work?

Thanks a lot!

RE: Highlighting the right margin

[Drew Adams]

    I've been trying to make an .el file I downloaded to work so I can see
    where the right margin starts to avoid coding long lines.

    The file is highlight-beyond-fill-column.el, and I have this line in my
    .emacs

    (require 'highlight-beyond-fill-column)

    But after restarting emacs (22.0.50 on Mac OS X), hitting M-X and then
    trying to invoke the function highlight-beyond-fill-column, I couldn't
    find the function at all.

Does library highlight-beyond-fill-column.el have this in it?

  (provide 'highlight-beyond-fill-column)

For your `require' to work, the library must `provide' the corresponding
feature. If the library has a `provide' call with a different feature name,
use that name in your `require'. If it has no `provide', either add one to
the library or use `load-library' instead of `require', in your .emacs.
`load-library' uses the file name (sans extension); `require' uses a
provided-feature name. HTH.

Re: Highlighting the right margin

[fortepianissimo]

The file highlight-beyond-fill-column.el does have this line at the
very end:

(provide 'highlight-beyond-fill-column)

But I did try both of these in my .emacs, but neither worked:

(require 'highlight-beyond-fill-column)

or

(load-library "highlight-beyond-fill-column")

Now the .el file came with a tarball I obtained called
emacs-goodies-el-24.15, and I just dropped the file in my

/usr/local/share/emacs/site-lisp

Other .el files deposited in that dir have been working great for me.

Any other suggestions? Thanks!

Re: Highlighting the right margin

[rgb]

> But I did try ...
>
> (load-library "highlight-beyond-fill-column")
>
There is almost certainly something in your *messages*
buffer that explains why it's not working.  Did you
look thoroughly?
Something like (message "<<< Look here >>>") just before you
load the functions should make anything relevant easier
to find.

RE: Highlighting the right margin

[Drew Adams]

    highlight-beyond-fill-column.el does have this line
    (provide 'highlight-beyond-fill-column)

And you tried:
    (require 'highlight-beyond-fill-column)
    (load-library "highlight-beyond-fill-column")

    Now the .el file came with a tarball I obtained called
    emacs-goodies-el-24.15, and I just dropped the file in my
    /usr/local/share/emacs/site-lisp
    Other .el files deposited in that dir have been working great for me.

1. If other libraries in that dir work, then that dir must be in your
`load-path', but check that variable anyway, to make sure.

2. Make sure the `provide' is at the top level of the file, so it is
evaluated by loading.

3. Verify that the `require' or `load-library' is in fact getting evaluated
in your .emacs. Check buffer *Messages* to see if there is a message
indicating that a load was tried but the library could not be loaded. If
not, double-check your .emacs code.

4. Load the file manually, after entering Emacs:

 `M-x load-library RET highlight-beyond-fill-column

If that works, the library is in your load-path, and it should also work in
your .emacs. If it doesn't work, the directory with the library is not in
your load-path.

5. Try to load manually by feature name, not library name:

 `M-: (require 'highlight-beyond-fill-column)

If that works, then the `provide' is working. If that doesn't work, but #4
worked, then the `provide' is not working, for some reason - check it
closer, in the file.

6. Double-check your spelling.

7. Make an sacrificial offering to the EmacsWiki.

HTH.

Re: Highlighting the right margin

[fortepianissimo]

Thanks for everyone who have replied - it turns out it has been working
all along!

After taking a closer look at highlight-beyond-fill-column.el, it
mentioned two bits:

;; Example usage:
;;
;; Customize the `highlight-beyond-fill-column-in-modes' variable to
;; setup the list of modes in which to highlight-beyond-fill-column
;;
;; Customize the `highlight-beyond-fill-column-face' variable to
;; to setup the face used for highlight-beyond-fill-column

So I did a customize-variable on highlight-beyond-fill-column-in-modes
and made it look like this in my .emacs

(custom-set-variables
...
 '(highlight-beyond-fill-column-in-modes (quote ("text-mode"
"python-mode")))
...)

Now when I loaded a Python script, I can see all the text overflowing
into the right margin is underlined - this is definitely different from
the effect I was expecting (in my imagination the entire region right
to the right margin should be painted with a different shade of color).

And another odd thing: this doesn't work in text-mode (under
Python-mode it works fine).

So it's like one problem solved but two are remained. Any more
suggestions? Thanks!