After check your source code, I finally and with your theory:

> Org doesn't load automatically.. it autoloads only if you open an Org
file or call an org-loading function. After emacs -Q, if you do M-:
(featurep 'org), you will get nil. So the user does get a change to set the
load path as they want before any package gets loaded.

I finally understand how it works. Yesterday, I use a crude way: delete
Emacs built-in org/ directory. This works too. But I still take your
method. Your method is the correct way. Thanks very much.

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On Wed, Jan 24, 2018 at 12:15 AM, Kaushal Modi <kaushal.modi@gmail.com>
wrote:

> On Tue, Jan 23, 2018 at 11:09 AM numbchild@gmail.com <numbchild@gmail.com>
> wrote:
>
>> Thanks for your advice. After your code inspiration. I got an idea. After
>> test, it works fine. I try to load `use-package` and `(use-package org :pin
>> manaul ..)` ahead of `(package-initialize)`. Half of the problem is solved.
>>
>
>
>> The another half of the problem is that Emacs still will load built-in
>> org-mode in lisp/org/. I think I can't solve this problem essentially.
>> Because I can't load before Emacs built-in library. Oops.
>>
>
> Org doesn't load automatically.. it autoloads only if you open an Org file
> or call an org-loading function. After emacs -Q, if you do M-: (featurep
> 'org), you will get nil. So the user does get a change to set the load path
> as they want before any package gets loaded.
>
> That's way, I tweak the load-path in the :preface section[1] in the org
> use-package form. The load-path would be set exactly as I want before org
> gets (auto)loaded.
>
> [1]: https://github.com/kaushalmodi/.emacs.d/blob/
> master/setup-files/setup-org.el
>
>
> --
>
> Kaushal Modi
>