how to check if xyz-mode is on load path?

how to check if xyz-mode is on load path?

[Xah Lee]

how can i check if a package already exists in the load path?

what i want to do is to put a package into autoload, but don't do that
if that package is already included in user's load path (e.g. either
the package is included in the emacs version she's got, or she already
installed it herself).

e.g. pseudo code:

(when
    (not (isPackageInstalledQ "ocaml-mode"))
  (autoload ocaml-mode "~/xahdir/ocaml-mode" )
)

Thanks

  Xah
∑ http://xahlee.org/

☄

Re: how to check if xyz-mode is on load path?

[B. T. Raven]

Xah Lee wrote:
> how can i check if a package already exists in the load path?
> 
> what i want to do is to put a package into autoload, but don't do that
> if that package is already included in user's load path (e.g. either
> the package is included in the emacs version she's got, or she already
> installed it herself).
> 
> e.g. pseudo code:
> 
> (when
>     (not (isPackageInstalledQ "ocaml-mode"))
>   (autoload ocaml-mode "~/xahdir/ocaml-mode" )
> )
> 
> Thanks
> 
>   Xah
> ∑ http://xahlee.org/
> 
> ☄

C-h v load-path

Re: how to check if xyz-mode is on load path?

[Lennart Borgman]

On Mon, Mar 2, 2009 at 5:48 AM, Xah Lee <xahlee@gmail.com> wrote:
> how can i check if a package already exists in the load path?
>
> what i want to do is to put a package into autoload, but don't do that
> if that package is already included in user's load path (e.g. either
> the package is included in the emacs version she's got, or she already
> installed it herself).
>
> e.g. pseudo code:
>
> (when
>    (not (isPackageInstalledQ "ocaml-mode"))
>  (autoload ocaml-mode "~/xahdir/ocaml-mode" )
> )


locate-library


> Thanks
>
>  Xah
> ∑ http://xahlee.org/
>
> ☄
>

Re: how to check if xyz-mode is on load path?

[Michael Ekstrand]

Xah Lee <xahlee@gmail.com> writes:
> how can i check if a package already exists in the load path?
>
> what i want to do is to put a package into autoload, but don't do that
> if that package is already included in user's load path (e.g. either
> the package is included in the emacs version she's got, or she already
> installed it herself).
>
> e.g. pseudo code:
>
> (when
>     (not (isPackageInstalledQ "ocaml-mode"))
>   (autoload ocaml-mode "~/xahdir/ocaml-mode" )
> )

locate-library will tell you if the library is available on the load
path; it will return a file name or nil.  featurep (on the package's
primary provided feature) or fboundp (on some relevant function's
symbol) can be used to test if it has already been loaded.

I would also pair the tests such that locate-library failing results in
the package being added to the load path, and featurep/fboundp results
in loading.  The package existing in the load path does not mean it has
been loaded/autoloaded, so just testing with locate-library in your code
above can result in the package not being loaded.

- Michael

-- 
mouse, n: A device for pointing at the xterm in which you want to type.
Confused by the strange files?  I cryptographically sign my messages.
For more information see <http://www.elehack.net/resources/gpg>.

Re: how to check if xyz-mode is on load path?

[Alan Mackenzie]

In comp.emacs Xah Lee <xahlee@gmail.com> wrote:
> how can i check if a package already exists in the load path?

M-x locate-library wil do it.

> Thanks

>  Xah

-- 
Alan Mackenzie (Nuremberg, Germany).

Re: how to check if xyz-mode is on load path?

[Kevin Rodgers]

Xah Lee wrote:
> how can i check if a package already exists in the load path?
> 
> what i want to do is to put a package into autoload, but don't do that
> if that package is already included in user's load path (e.g. either
> the package is included in the emacs version she's got, or she already
> installed it herself).
> 
> e.g. pseudo code:
> 
> (when
>     (not (isPackageInstalledQ "ocaml-mode"))
>   (autoload ocaml-mode "~/xahdir/ocaml-mode" )
> )

(fboundp 'ocaml-mode)

-- 
Kevin Rodgers
Denver, Colorado, USA