Re: Requiring elisp that comes with Emacs

[Eric Abrahamsen <eric@ericabrahamsen.net>]

Narendra Joshi <narendraj9@gmail.com> writes:

> Skip Montanaro <skip.montanaro@gmail.com> writes:
>
>> On Mon, Jan 30, 2017 at 10:52 AM, Narendra Joshi <
>> narendraj9@gmail.com> wrote:
>>
>>     What happens when we do `require'?
>>
>>
>> It guarantees the relevant feature is available, generally as a side
>> effect of loading the named package. I believe the package much
>> "provide" its name. If not found, an error is raised. Full details
>> can be found here:
>>
>> https://www.gnu.org/software/emacs/manual/html_node/elisp/
>> Named-Features.html
>
> My question was more about whether we need to `require` packages that
> come with Emacs itself, e.g. org-mode.

Practically speaking, every package that come with Emacs will provide
autoload statements for all the common entrypoint functions. Calling
`require' will instantly load all the package's code, and all the
packages it requires. Autoload, on the other hand, will leave the
package unloaded, but load it automatically the first time you use an
autoload'ed function. Most of the time, that's all you need.

Eric