File for minor mode not found

[fatiparty--- via Users list for the GNU Emacs text editor <help-gnu-emacs@gnu.org>]

Jan 9, 2022, 16:01 by stephen.berman@gmx.net:

> On Sun, 9 Jan 2022 16:46:51 +0100 (CET) fatiparty--- via Users list for the GNU Emacs text editor <help-gnu-emacs@gnu.org> wrote:
>
>> Jan 9, 2022, 15:12 by stephen.berman@gmx.net:
>>
>>> On Sun, 9 Jan 2022 15:43:42 +0100 (CET) fatiparty--- via Users list for the
>>> GNU Emacs text editor <help-gnu-emacs@gnu.org> wrote:
>>>
> [...]
>
>>>> It does not exist.  The file is named daph-ideograms.el but I am using 
>>>> (provide 'daph) at the end of the file.  And using (require 'daph) after 
>>>> setting the load-path in another file.
>>>>
>>>
>>> That should be (require 'daph "daph-ideograms"), see `C-h f require':.
>>>
>>>  require is a built-in function in ‘C source code’.
>>>  
>>>  (require FEATURE &optional FILENAME NOERROR)
>>>  
>>>  If feature FEATURE is not loaded, load it from FILENAME.
>>>  If FEATURE is not a member of the list ‘features’, then the feature is
>>>  not loaded; so load the file FILENAME.
>>>  
>>>  If FILENAME is omitted, the printname of FEATURE is used as the file
>>>  name, and ‘load’ will try to load this name appended with the suffix
>>>  ‘.elc’, ‘.el’, or the system-dependent suffix for dynamic module
>>>  files, in that order.
>>>
>>> Steve Berman
>>>
>>
>> Thanks Steve.  One thing that has been difficult to see, is the
>> relationship between (provide 'daph) and (require 'daph).  Following
>> your suggestion, I need to have (require 'daph "daph-ideograms").  Are
>> there any implications for the (provide 'daph) part?
>>
>
> No, that's fine.  As its doc string says, `provide' just "[a]nnounce[s]
> that FEATURE is a feature of the current Emacs."  So there's no
> requirement that FEATURE be the name of an existing file.  But `require'
> loads a feature from an existing file, so it has to find that file,
> using the name of the feature as a default.  But if the file providing
> that feature has a different name, you have to pass that name (just the
> base name without extension) to `require'.
>
> Steve Berman
>
I have difficulty about the utility of 'provide'.  You have pointed out that (provide 'daph)
simply announces that daph is a feature of the current emacs.  Can it be any name?  The 
manual states that "calling 'provide' adds 'feature' tothe front of 'features' if it is not already
 in that list".  This suggests that provide should also use  (provide 'daph-ideograms).  

I guess that one could define the feature as 'daph' when using 'provide'.  And use the feature 'daph'
when calling 'require'.  In this way, the 'daph' will be recognise the 'daph' feature in the features variable,
but use the optional filename "daph-ideograms"

Thus

daph-ideograms.el
**********************
  (provide 'daph)

test.el
******* 
  (add-to-list
      'load-path "~/Admin/bin/gadi-1.0/typex/ziggurat-protowrit/daph-ideograms")
   ;; Load the Daph Package if it has not already been loaded.
   (require 'daph "daph-ideograms")

--------

My load path is quite long, and wonder how this can be shortened by storing in some other variable
before passing to 'add-to-list'.