bug#20322: 25.0.50; indent-tabs-mode should default to nil

[Dmitry Gutov <dgutov@yandex.ru>]

On 04/17/2015 10:26 AM, Eli Zaretskii wrote:

> Yes, I know that.  I'm saying that this default doesn't bother me, as
> long as the modes that I care about still default to non-nil.

It seems that you won't object to changes as long as they don't affect 
your our experience, even if you'd just have to change one line in your 
init.el.

I mentioned the default value because it's a technical consideration.

> I meant "need" as in "most users of that language already use spaces".

So, you're open to considering C and C++ in this context, too?

> I don't consider GitHub to be a representative sample for this matter.

Maybe not, but it's a sample we can research. And Emacs could do worse 
than become more friendly to the modern-ish audience.

Do you have a better sample in mind?

> I don't see any complications.  Doesn't everyone have their own hooks
> for every language they use, anyway?  I know I do, since almost the
> first day I started using Emacs.  That hook is the place where users
> could customize the variable, if they don't the defaults.

The members of those "everyone" shouldn't be bothered with a change in 
one tiny default value anyway.

I think you're overestimating the savvy-ness of an average Emacs user. 
Not every beginner is fine with writing Elisp (some spend years without 
doing so), and the more effort a user's first steps in Emacs take, the 
more likely they are to settle for something else, because they haven't 
yet been properly exposed to Emacs's benefits yet.

That's why I think the default are important, and that they shouldn't 
take the entrenched user base so much into account.

> See above; and it doesn't have to be a lambda function, of course.
> Mine has a name (my-c-stuff, if you want to know) and a doc string.

I also use hooks quite a bit in my init script.

> We are talking about programmers, for whom having a mode hook is not a
> problem.

Not necessarily Emacs Lisp programmers, though.

> I'm actually guessing they already have such a hook anyway;
> I cannot see how one can use a programming-language mode without a lot
> of customizations, and the place to do that is in a mode hook.  This
> is normal, routine practice in Emacs.

The user options (and the Customize interface; I think we haven't given 
up on it yet) should cover the core of what a user might want to change.

Here's the sum total of my current ruby-mode tweaks. One 
`eval-after-load', but no custom functions in ruby-mode-hook:

(add-hook 'ruby-mode-hook 'flycheck-mode)
(add-hook 'ruby-mode-hook 'robe-mode)

(eval-after-load 'ruby-mode
   '(progn
      (define-key ruby-mode-map (kbd "C-c :") 'ruby-toggle-hash-syntax)
      (require 'ruby-end)))

Plus a few installed packages, some of which use `add-hook' at the top 
level. I do have one related `add-hook' with a lambda commented out 
currently, but it's also tiny, and the above provide a satisfactory 
experience already.

> I gave you my personal statistics on that: most of them use tabs.  And
> I personally get annoyed whenever a project asks me to untabify my
> submissions (but abide, of course).

Untabifying (or tabifying) should happen automatically, via 
project-local settings. There's even a cross-editor specification (as 
well as an Emacs package) for this: http://editorconfig.org/