On August 4, 2019 12:31:59 AM GMT+02:00, Juri Linkov <juri@linkov.net> wrote:
(log-edit-mode . ((log-edit-font-lock-gnu-style . t)
- (log-edit-setup-add-author . t)))
+ (log-edit-setup-add-author . t)
+ (display-fill-column-indicator-column . 78)
+ (eval . (display-fill-column-indicator-mode))))
This will cause an annoying message and prompt when editing Emacs
sources with an Emacs which doesn't yet have
display-fill-column-indicator-mode, right? Can we avoid that? I
routinely need to work on the latest sources with an older Emacs.
Shouldn't local-variables functions ignore undefined variables and commands?
Probably not, since such change won't help for older versions.
Right, and we cannot summarily allow any variables a given Emacs
doesn't know about, that'd we unsafe.
Actually by using the word "ignore" I meant to not set an unbound variable
(currently `hack-local-variables' defines and sets unbound variables).
But this is not backward-compatible change.
Then one way is to put such lines to the init file
to avoid typing `y' to confirm local variables
while using emacs-26 to commit emacs-27 changes:
Rather than requiring users of older Emacsen to change their init
files in such strange ways, which will/might be a problem when they
upgrade to Emacs 27, why not expect users who want the early detection
of long lines to turn on display-fill-column-indicator-mode in their
init files? IOW, the solution that requires changes to one's init
files goes both ways.
I don't understand why display-fill-column-indicator customization
should be more complicated than necessary? Why it requires adding
these lines:
(display-fill-column-indicator-column . 78)
(eval . (display-fill-column-indicator-mode))
when it should be enough to avoid eval by:
(display-fill-column-indicator-column . 78)
(display-fill-column-indicator . t)
Is it because the only purpose of display-fill-column-indicator-mode
is to set display-fill-column-indicator-character? But then why
display-fill-column-indicator-character is not nil by default?
This contradicts the docstring of display-fill-column-indicator-character
that says that the default is U+2502, but actually the default is nil.
I'm CC-ing the author of display-fill-column-indicator:
Could you please consider setting the default value of
display-fill-column-indicator-character? This could
simplify customization.