Re: Very basic questions.

["Colin S. Miller" <no-spam-thank-you@csmiller.demon.co.uk>]

jronald wrote:
> "Colin S. Miller" <no-spam-thank-you@csmiller.demon.co.uk> 
> ??????:450bdfd3$0$75037$14726298@news.sunsite.dk...
>>> In runtime, how does "require" know where the feature list is? There is 
>>> only machine code then.
>>>
>> John,
>>
>> (require 'feature)
>> searches the paths listed in 'load-path',
>> this can be added to using (add-path).
>> It looks for a file called "feature.el" or "feature.elc".
>>
>>
> Do you mean that "provide" modifies the files, both .el and .elc? I just 
> can't imagine.
John,

(require 'feature) loads the package 'feature' into
Emacs's memory, it doesn't modify the source,
or pre-compiled package, it just reads them.

(provide 'feature),
which is at the end of 'feature.el', confirms that the
package "feature" has been loaded; this makes a subsequent
(require 'feature) a no-operation command.

A feature is normally provided by a source file
of the same name as the feature, but can
be provided by a different file, by using
(require 'feature "feature-mode")
In this cause "feature-mode.el" or "feature-mode.elc"
will be loaded, they should have a
(provide 'feature) at the end.


To compile a source package into its .elc,
run (byte-compile-file) on it. This
is done when Emacs is compiled from its sources,
and unless you are writing your own packages,
you shouldn't need to use it.

HTH,
Colin S. Miller