Saving variables for use between emacs sessions

Saving variables for use between emacs sessions

[uzibalqa]

How can I save variable that can be reused between emacs sessions?

RE: [External] : Saving variables for use between emacs sessions

[Drew Adams]

> How can I save variable that can be reused between emacs sessions?

Lots of ways. Some:

1. savehist.el
2. desktop.el
3. Bookmark+ bookmark variable-list bookmark

https://www.emacswiki.org/emacs/BookmarkPlus#FunctionSequenceVarlistBookmarks

4. If it's a user option (defcustom), then in your `custom-file' (or init file).

Re: [External] : Saving variables for use between emacs sessions

[Robert Pluim]

>>>>> On Thu, 15 Sep 2022 11:46:57 +0000, Drew Adams <drew.adams@oracle.com> said:

    >> How can I save variable that can be reused between emacs sessions?
    Drew> Lots of ways. Some:

    Drew> 1. savehist.el
    Drew> 2. desktop.el
    Drew> 3. Bookmark+ bookmark variable-list bookmark

    Drew> https://www.emacswiki.org/emacs/BookmarkPlus#FunctionSequenceVarlistBookmarks

    Drew> 4. If it's a user option (defcustom), then in your `custom-file' (or init file).

And in emacs-29, `define-multisession-variable', although thatʼs
intended more for packages than user config.

Robert
-- 

Re: [External] : Saving variables for use between emacs sessions

[Marcin Borkowski]

On 2022-09-15, at 14:49, Robert Pluim <rpluim@gmail.com> wrote:

>>>>>> On Thu, 15 Sep 2022 11:46:57 +0000, Drew Adams <drew.adams@oracle.com> said:
>
>     >> How can I save variable that can be reused between emacs sessions?
>     Drew> Lots of ways. Some:
>
>     Drew> 1. savehist.el
>     Drew> 2. desktop.el
>     Drew> 3. Bookmark+ bookmark variable-list bookmark
>
>     Drew> https://www.emacswiki.org/emacs/BookmarkPlus#FunctionSequenceVarlistBookmarks
>
>     Drew> 4. If it's a user option (defcustom), then in your `custom-file' (or init file).
>
> And in emacs-29, `define-multisession-variable', although thatʼs
> intended more for packages than user config.

Also, the `persist' package.

-- 
Marcin Borkowski
http://mbork.pl

RE: [External] : Saving variables for use between emacs sessions

[Drew Adams]

And of course there's just writing one or more
variable values to a separate file, on your own.

As I said, there are _lots_ of ways to save var
values persistently.

OP's request was far too vague.  "How can I save
a value?" is about as unspecific as it gets...

Re: [External] : Saving variables for use between emacs sessions

[uzibalqa]

Sent with Proton Mail secure email.

------- Original Message -------
On Thursday, September 15th, 2022 at 1:26 PM, Marcin Borkowski <mbork@mbork.pl> wrote:


> On 2022-09-15, at 14:49, Robert Pluim rpluim@gmail.com wrote:
> 
> > > > > > > On Thu, 15 Sep 2022 11:46:57 +0000, Drew Adams drew.adams@oracle.com said:
> > 
> > >> How can I save variable that can be reused between emacs sessions?
> > Drew> Lots of ways. Some:
> > 
> > Drew> 1. savehist.el
> > Drew> 2. desktop.el
> > Drew> 3. Bookmark+ bookmark variable-list bookmark
> > 
> > Drew> https://www.emacswiki.org/emacs/BookmarkPlus#FunctionSequenceVarlistBookmarks
> > 
> > Drew> 4. If it's a user option (defcustom), then in your `custom-file' (or init file).
> > 
> > And in emacs-29, `define-multisession-variable', although thatʼs
> > intended more for packages than user config.
> 
> 
> Also, the `persist' package.

Right, I want to have a user option, but although I want to allow a user to set the value,
I also would like to set a value in an automatic way, using a function that does the 
necessary calculations, and stares the answer in the variable.

How does one let a user change a value, and how can I save it automatically as well?

RE: [External] : Saving variables for use between emacs sessions

[Drew Adams]

> Right, I want to have a user option, but although I want to allow a user
> to set the value,
> I also would like to set a value in an automatic way, using a function
> that does the
> necessary calculations, and stares the answer in the variable.
> 
> How does one let a user change a value, and how can I save it
> automatically as well?

Just define the option with defcustom.

Users can use Customize to change the
value and save that new setting to their
`custom-file' or init file.

Or they can use `custom*' functions to
set and to save.  Or you can use such
functions to do that for them "in an
automatic way".

Just look into what's available - it's
all there.  You, yourself, can easily
check it out.

RE: [External] : Saving variables for use between emacs sessions

[uzibalqa]

------- Original Message -------
On Thursday, September 15th, 2022 at 5:23 PM, Drew Adams <drew.adams@oracle.com> wrote:


> > Right, I want to have a user option, but although I want to allow a user
> > to set the value,
> > I also would like to set a value in an automatic way, using a function
> > that does the
> > necessary calculations, and stares the answer in the variable.
> > 
> > How does one let a user change a value, and how can I save it
> > automatically as well?
> 
> 
> Just define the option with defcustom.
> 
> Users can use Customize to change the
> value and save that new setting to their
> `custom-file' or init file. Or they can use` custom*' functions to
> set and to save. Or you can use such
> functions to do that for them "in an
> automatic way".
> 
> Just look into what's available - it's
> all there. You, yourself, can easily
> check it out.

I have coded as follows

(defgroup tpframe-pos nil

  "Set position of frame."

  :group 'convenience)

(defcustom tpfxpos 8

  "X position of initial frame."

  :group 'tpframe-pos

  :type 'integer)

(defcustom tpfypos 8

  "Y position of initial frame."

  :group 'tpframe-pos

  :type 'integer)

Then I have a function that changes the values with

(setq tpfxpos nlft) and (setq tpfypos ntop)

The difficulty that that after I run another the command emacs again in from terminal,
the values updated by the function are not reflected in `M-x customize-group`.

RE: [External] : Saving variables for use between emacs sessions

[Drew Adams]

> > Just define the option with defcustom.
> >
> > Users can use Customize to change the
> > value and save that new setting to their
> > `custom-file' or init file. Or they can use` custom*' functions to
> > set and to save. Or you can use such
> > functions to do that for them "in an
> > automatic way".
> >
> > Just look into what's available - it's
> > all there. You, yourself, can easily
> > check it out.
> 
> I have coded as follows
> (defgroup tpframe-pos nil
>   "Set position of frame."
>   :group 'convenience)
> (defcustom tpfxpos 8
>   "X position of initial frame."
>   :group 'tpframe-pos :type 'integer)
> (defcustom tpfypos 8
>   "Y position of initial frame."
>   :group 'tpframe-pos :type 'integer)
> 
> Then I have a function that changes the values with
> (setq tpfxpos nlft) and (setq tpfypos ntop)

What part of this:

> > use `custom*' functions to set and to save.
        ^^^^^^^^^                         ^^^^

did you not understand?  Or did you just ignore
it all?

Do you think `setq' is a `custom*' function?
Do you think it saves the variable value
persistently?

RE: [External] : Saving variables for use between emacs sessions

[uzibalqa]

------- Original Message -------
On Friday, September 16th, 2022 at 2:19 AM, Drew Adams <drew.adams@oracle.com> wrote:


> > > Just define the option with defcustom.
> > > 
> > > Users can use Customize to change the
> > > value and save that new setting to their
> > > `custom-file' or init file. Or they can use` custom*' functions to
> > > set and to save. Or you can use such
> > > functions to do that for them "in an
> > > automatic way".
> > > 
> > > Just look into what's available - it's
> > > all there. You, yourself, can easily
> > > check it out.
> > 
> > I have coded as follows
> > (defgroup tpframe-pos nil
> > "Set position of frame."
> > :group 'convenience)
> > (defcustom tpfxpos 8
> > "X position of initial frame."
> > :group 'tpframe-pos :type 'integer)
> > (defcustom tpfypos 8
> > "Y position of initial frame."
> > :group 'tpframe-pos :type 'integer)
> > 
> > Then I have a function that changes the values with
> > (setq tpfxpos nlft) and (setq tpfypos ntop)
> 
> 
> What part of this:
> 
> > > use `custom*' functions to set and to save.
> 
> ^^^^^^^^^ ^^^^
> 
> did you not understand? Or did you just ignore
> it all?
> 
> Do you think `setq' is a` custom*' function?
> Do you think it saves the variable value
> persistently?

I do not understand.  Once I define a variable with the declaration "defcustom",
how can I make a function change the value?

Re: [External] : Saving variables for use between emacs sessions

[Jean Louis]

* uzibalqa <uzibalqa@proton.me> [2022-09-16 05:42]:
> I do not understand.  Once I define a variable with the declaration "defcustom",
> how can I make a function change the value?

Hyperbole link:
{C-h f defcustom RET}

where it says:

This macro calls ‘custom-declare-variable’.  If you want to
programmatically alter a customizable variable (for instance, to
write a package that extends the syntax of a variable), you can
call that function directly.

Hyperbole link:

{C-h f custom-declare-variable RET}

(custom-declare-variable SYMBOL DEFAULT DOC &rest ARGS)

Like ‘defcustom’, but SYMBOL and DEFAULT are evaluated as normal arguments.
DEFAULT should be an expression to evaluate to compute the default value,
not the default value itself.

That way you can programmatically change variables created by
`defcustom'.

-- 
Jean

Take action in Free Software Foundation campaigns:
https://www.fsf.org/campaigns

In support of Richard M. Stallman
https://stallmansupport.org/

Re: [External] : Saving variables for use between emacs sessions

[uzibalqa]

------- Original Message -------
On Friday, September 16th, 2022 at 7:30 AM, Jean Louis <bugs@gnu.support> wrote:


> * uzibalqa uzibalqa@proton.me [2022-09-16 05:42]:
> 
> > I do not understand. Once I define a variable with the declaration "defcustom",
> > how can I make a function change the value?
> 
> 
> Hyperbole link:
> {C-h f defcustom RET}
> 
> where it says:
> 
> This macro calls ‘custom-declare-variable’. If you want to
> programmatically alter a customizable variable (for instance, to
> write a package that extends the syntax of a variable), you can
> call that function directly.
> 
> Hyperbole link:
> 
> {C-h f custom-declare-variable RET}
> 
> (custom-declare-variable SYMBOL DEFAULT DOC &rest ARGS)
> 
> Like ‘defcustom’, but SYMBOL and DEFAULT are evaluated as normal arguments.
> DEFAULT should be an expression to evaluate to compute the default value,
> not the default value itself.
> 
> That way you can programmatically change variables created by
> `defcustom'.

I would need some help with using it, particularly with using SYMBOL, and DEFAULT where
the value itself cannot be used.

For instance

(defgroup frame-pos nil

  "Set position of frame."

  :group 'convenience)

(defcustom fxpos 8

  "X position of initial frame."

  :type 'integer

  :group 'frame-pos)

This is the function that should update the value in defcustom 

(defun frame-shift (frame)

  (let* ( (lft (car (frame-position)))

          (wdt (frame-outer-width frame))

	  (nlft (+ lft (/ wdt 2))) )

    (set-frame-position frame nlft ntop)

    (custom-declare-variable 'typex-fxpos nlft)) )