bug#38696: "If you edit it by hand, you could mess it up"

bug#38696: "If you edit it by hand, you could mess it up"

[積丹尼 Dan Jacobson]

Here's a problem that I think illustrates a departure from Dr.
Stallman's original goals (which include to keep the user "in the know",
"in control.")

Let's say the user wants to make the font bigger.
In emacs he goes into the menu bar and picks "Options" > "Set
Default Font", makes it bigger, and then chooses "Save Options", which
pastes some "custom-set" code into his .emacs file
that even contains a warning "If you edit it by hand, you could mess it up",
meaning for the rest of his life he should just play it safe and stick
with the menus.

It might as well just paste some compiled bytecode in there.
There isn't even any good old fashioned setq versions the user could
learn with and expand left around in any temporary buffer. Nor is there
any decompiler command provided.

bug#38696: "If you edit it by hand, you could mess it up"

[Phil Sainty]

On 21/12/19 1:02 PM, 積丹尼 Dan Jacobson wrote:
> that even contains a warning "If you edit it by hand, you could mess
> it up", meaning for the rest of his life he should just play it safe
> and stick with the menus.

It neither says (nor even hints) that this will be the case "for the
rest of [your] life".  I think it implies that it's possible to avoid
messing it up, provided that you know what you're doing; which in turn
suggests that you might learn how to do that.

Like everything else in Emacs, you can use the documentation and code
in order to gain that understanding, if you choose to.  For those who
choose not to, the warning serves a valuable purpose.


-Phil

bug#38696: "If you edit it by hand, you could mess it up"

[積丹尼 Dan Jacobson]

No. It could offer:
"Would you like instead some simple lisp that you can modify by hand
later? Even if it might not be as efficient?"

Or it could just add the simple lisp version in a comment below its
"custom-set" version without asking the user.

Or it could document a decompiler.

bug#38696: "If you edit it by hand, you could mess it up"

[Richard Stallman]

[[[ To any NSA and FBI agents reading my email: please consider    ]]]
[[[ whether defending the US Constitution against all enemies,     ]]]
[[[ foreign or domestic, requires you to follow Snowden's example. ]]]

  > Let's say the user wants to make the font bigger.
  > In emacs he goes into the menu bar and picks "Options" > "Set
  > Default Font", makes it bigger, and then chooses "Save Options", which
  > pastes some "custom-set" code into his .emacs file
  > that even contains a warning "If you edit it by hand, you could mess it up",
  > meaning for the rest of his life he should just play it safe and stick
  > with the menus.

Would you please show us what this looks like?

-- 
Dr Richard Stallman
Founder, Free Software Foundation (https://gnu.org, https://fsf.org)
Internet Hall-of-Famer (https://internethalloffame.org)

bug#38696: "If you edit it by hand, you could mess it up"

[積丹尼 Dan Jacobson]

>>>>> "RMS" == Richard Stallman <rms@gnu.org> writes:

RMS> Would you please show us what this looks like?

$ cat .emacs
(custom-set-variables
 ;; custom-set-variables was added by Custom.
 ;; If you edit it by hand, you could mess it up, so be careful.
 ;; Your init file should contain only one such instance.
 ;; If there is more than one, they won't work right.
 )
(custom-set-faces
 ;; custom-set-faces was added by Custom.
 ;; If you edit it by hand, you could mess it up, so be careful.
 ;; Your init file should contain only one such instance.
 ;; If there is more than one, they won't work right.
 '(default ((t (:family "DejaVu Sans Mono" :foundry "PfEd" :slant normal :weight normal :height 218 :width normal)))))

There is no way offered to "decompile" this into something that all
those Emacs manuals talk about when introducing how to edit your .emacs
file.

The user is no longer in full control, but must maintain it via an
interface (the menus.)

bug#38696: "If you edit it by hand, you could mess it up"

[arthur miller]

[-- Attachment #1: Type: text/plain, Size: 1643 bytes --]

> The user is no longer in full control, but must > maintain it via an
> interface (the menus.)

Actually it says "you should be careful". It does not says you should never edit it. I don't think you have reason to edit it by hand, especially if you redirect customize saves to different file then your init, but you certainly can if you wish (and know what you are doing).




-------- Originalmeddelande --------
Från: 積丹尼 Dan Jacobson <jidanni@jidanni.org>
Datum: 2019-12-22 01:37 (GMT+01:00)
Till: Richard Stallman <rms@gnu.org>
Kopia: 38696@debbugs.gnu.org
Ämne: bug#38696: "If you edit it by hand, you could mess it up"

>>>>> "RMS" == Richard Stallman <rms@gnu.org> writes:

RMS> Would you please show us what this looks like?

$ cat .emacs
(custom-set-variables
 ;; custom-set-variables was added by Custom.
 ;; If you edit it by hand, you could mess it up, so be careful.
 ;; Your init file should contain only one such instance.
 ;; If there is more than one, they won't work right.
 )
(custom-set-faces
 ;; custom-set-faces was added by Custom.
 ;; If you edit it by hand, you could mess it up, so be careful.
 ;; Your init file should contain only one such instance.
 ;; If there is more than one, they won't work right.
 '(default ((t (:family "DejaVu Sans Mono" :foundry "PfEd" :slant normal :weight normal :height 218 :width normal)))))

There is no way offered to "decompile" this into something that all
those Emacs manuals talk about when introducing how to edit your .emacs
file.

The user is no longer in full control, but must maintain it via an
interface (the menus.)




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bug#38696: "If you edit it by hand, you could mess it up"

[Eli Zaretskii]

> From: 積丹尼 Dan Jacobson
>  <jidanni@jidanni.org>
> Date: Sun, 22 Dec 2019 08:35:54 +0800
> Cc: 38696@debbugs.gnu.org
> 
> >>>>> "RMS" == Richard Stallman <rms@gnu.org> writes:
> 
> RMS> Would you please show us what this looks like?
> 
> $ cat .emacs
> (custom-set-variables
>  ;; custom-set-variables was added by Custom.
>  ;; If you edit it by hand, you could mess it up, so be careful.
>  ;; Your init file should contain only one such instance.
>  ;; If there is more than one, they won't work right.
>  )
> (custom-set-faces
>  ;; custom-set-faces was added by Custom.
>  ;; If you edit it by hand, you could mess it up, so be careful.
>  ;; Your init file should contain only one such instance.
>  ;; If there is more than one, they won't work right.
>  '(default ((t (:family "DejaVu Sans Mono" :foundry "PfEd" :slant normal :weight normal :height 218 :width normal)))))
> 
> There is no way offered to "decompile" this into something that all
> those Emacs manuals talk about when introducing how to edit your .emacs
> file.

custom-set-variables and custom-set-faces are documented in the ELisp
manual, so, while the note about caution is in order (because not
every user knows Lisp), there's nothing magical about the above, no
more than some use of setq.

> The user is no longer in full control, but must maintain it via an
> interface (the menus.)

Only if the user chooses not to be in control.

bug#38696: "If you edit it by hand, you could mess it up"

[Drew Adams]

>> The user is no longer in full control, but must
>> maintain it via an interface (the menus.)
>
> Actually it says "you should be careful". It does
> not says you should never edit it. I don't think
> you have reason to edit it by hand, especially if
> you redirect customize saves to different file
> then your init, but you certainly can if you wish
> (and know what you are doing).

The most important message about this, for users,
is to let them know that this code is inserted
and _updated (overwritten) automatically_.

That's the _reason_ we warn users not to edit it.

It's not so much because their edits might mess
something up.  It's that they need to be aware
that editing it competes with automatic updating.
If you edit it then you are fighting against
Customize.

If you edit it, and if you never use Customize
(and no code you use ever uses Customize code),
then, yes, the only potential problem is that you
can mess things up for your future Emacs sessions.

But that's not the likeliest scenario.  The real,
more likely problem is that you make a change to
this code and later Customize overwrites your
change - and you might not be aware of that.

IMO, that's what this inserted comment is really
about: letting you know that the code is updated
automatically, and manual and automatic updating
don't mix well - each can overwrite the other.

 


-------- Originalmeddelande --------
Från: 積丹尼 Dan Jacobson <jidanni@jidanni.org> 
Datum: 2019-12-22 01:37 (GMT+01:00) 
Till: Richard Stallman <rms@gnu.org> 
Kopia: 38696@debbugs.gnu.org 
Ämne: bug#38696: "If you edit it by hand, you could mess it up" 

>>>>> "RMS" == Richard Stallman <rms@gnu.org> writes:

RMS> Would you please show us what this looks like?

$ cat .emacs
(custom-set-variables
 ;; custom-set-variables was added by Custom.
 ;; If you edit it by hand, you could mess it up, so be careful.
 ;; Your init file should contain only one such instance.
 ;; If there is more than one, they won't work right.
 )
(custom-set-faces
 ;; custom-set-faces was added by Custom.
 ;; If you edit it by hand, you could mess it up, so be careful.
 ;; Your init file should contain only one such instance.
 ;; If there is more than one, they won't work right.
 '(default ((t (:family "DejaVu Sans Mono" :foundry "PfEd" :slant normal :weight normal :height 218 :width normal)))))

There is no way offered to "decompile" this into something that all
those Emacs manuals talk about when introducing how to edit your .emacs
file.

The user is no longer in full control, but must maintain it via an
interface (the menus.)

bug#38696: "If you edit it by hand, you could mess it up"

[積丹尼 Dan Jacobson]

Warning or not, same .emacs file or not, the user still cannot touch it.
Sure he can. But then for the rest of his life he had better not do any
such saves from any menus.

bug#38696: "If you edit it by hand, you could mess it up"

[Richard Stallman]

[[[ To any NSA and FBI agents reading my email: please consider    ]]]
[[[ whether defending the US Constitution against all enemies,     ]]]
[[[ foreign or domestic, requires you to follow Snowden's example. ]]]

  > (custom-set-faces
  >  ;; custom-set-faces was added by Custom.
  >  ;; If you edit it by hand, you could mess it up, so be careful.
  >  ;; Your init file should contain only one such instance.
  >  ;; If there is more than one, they won't work right.
  >  '(default ((t (:family "DejaVu Sans Mono" :foundry "PfEd" :slant normal :weight normal :height 218 :width normal)))))

  > There is no way offered to "decompile" this into something that all
  > those Emacs manuals talk about when introducing how to edit your .emacs
  > file.

It isn't Lisp code.  It is just data, and the bulk of it is a plist
that is pretty obvious to edit.

It would be useful to explain the three outer levels of list structure.
A couple of lines of comment can explain that.
-- 
Dr Richard Stallman
Founder, Free Software Foundation (https://gnu.org, https://fsf.org)
Internet Hall-of-Famer (https://internethalloffame.org)

bug#38696: "If you edit it by hand, you could mess it up"

[積丹尼 Dan Jacobson]

You would also need to tell them how to clone it to a new variable that
would be safe from competition the next time they use such menus.

And emacs would need to know about this new variable, in order to run
items attached to it.

bug#38696: "If you edit it by hand, you could mess it up"

[Richard Stallman]

[[[ To any NSA and FBI agents reading my email: please consider    ]]]
[[[ whether defending the US Constitution against all enemies,     ]]]
[[[ foreign or domestic, requires you to follow Snowden's example. ]]]

  > But that's not the likeliest scenario.  The real,
  > more likely problem is that you make a change to
  > this code and later Customize overwrites your
  > change - and you might not be aware of that.

We could make Customize detect hand-editing by looking at the value
in .emacs and determining that it doesn't have a format Customize
could ever write?

Or we could the comment say, "If you want to edit this value by hand,
delete this comment."  Customize could interpret the absence of
that comment as meaning the value has been hand-edited.

Either way, Customize could then report a problem and offer a choice
of (1) deleting the value in the file, or (2) quitting.

-- 
Dr Richard Stallman
Founder, Free Software Foundation (https://gnu.org, https://fsf.org)
Internet Hall-of-Famer (https://internethalloffame.org)

bug#38696: "If you edit it by hand, you could mess it up"

[Drew Adams]

>   > But that's not the likeliest scenario.  The real,
>   > more likely problem is that you make a change to
>   > this code and later Customize overwrites your
>   > change - and you might not be aware of that.
> 
> We could make Customize detect hand-editing by looking at the value
> in .emacs and determining that it doesn't have a format Customize
> could ever write?
> 
> Or we could the comment say, "If you want to edit this value by hand,
> delete this comment."  Customize could interpret the absence of
> that comment as meaning the value has been hand-edited.
> 
> Either way, Customize could then report a problem and offer a choice
> of (1) deleting the value in the file, or (2) quitting.

I guess you're proposing that, if a user edits
what Customize puts in a user file (`custom-file'
or init file), then Customize could/should try to
detect that that has occurred.  And then Customize
could/should ask the user how to handle that
situation.

A priori that sounds complicated, and maybe error
prone, to me.  But maybe it's worth considering.

My suggestion would be to just change the comment
wording a bit, to make clear that future use of
Customize might overwrite any manual changes you
make to that code.  IOW, state that clearly as a
major reason _why_ you're advised not to edit the
code.

And as others have pointed out, future Customize
use might not always be obvious, interactive use
of `M-x customize-*' commands.

---

I'd also suggest that the inserted comment, and
the Emacs docs more generally, would do well to
suggest/advise that users use `custom-file', to
keep Customize-generated code separate from their
init files.

That's a good idea in general, IMO, and it would
go a long way toward avoiding the problem of
users editing such code, i.e., of users and
Customize stomping on each other.

---

I'd even suggest that if `custom-file' is
undefined then Customize should immediately ask
a user to define it, instead of just silently
writing to a user's init file.

At least, that could be done if Customize could
be sure there's not already any Customize code
in the init file.

But if an init file already has some Customize
code, then such a dialog becomes more delicate.
Customize might need to just advise moving such
existing code to the new `custom-file'.

Or if, as you suggest, it could detect its own
code then it could offer to move any such that's
in the init file to a `custom-file'.

bug#38696: "If you edit it by hand, you could mess it up"

[Richard Stallman]

[[[ To any NSA and FBI agents reading my email: please consider    ]]]
[[[ whether defending the US Constitution against all enemies,     ]]]
[[[ foreign or domestic, requires you to follow Snowden's example. ]]]

  > A priori that sounds complicated, and maybe error
  > prone, to me.  But maybe it's worth considering.

I am not trying to insist.

  > My suggestion would be to just change the comment
  > wording a bit, to make clear that future use of
  > Customize might overwrite any manual changes you
  > make to that code.  IOW, state that clearly as a
  > major reason _why_ you're advised not to edit the
  > code.

I agree that would be an improvement.

  > I'd even suggest that if `custom-file' is
  > undefined then Customize should immediately ask
  > a user to define it, instead of just silently
  > writing to a user's init file.

I think that would make Emacs usage a little more complicated
for lots of users, and only a few would benefit.

-- 
Dr Richard Stallman
Founder, Free Software Foundation (https://gnu.org, https://fsf.org)
Internet Hall-of-Famer (https://internethalloffame.org)

bug#38696: "If you edit it by hand, you could mess it up"

[積丹尼 Dan Jacobson]

Actually the comment should say
;; Like it? Well perhaps you might want a version of it that you can
;; maintain by hand! Just use "M-x customize-decustomize" on that region of
;; code to get a human-friendly-readable version that you can instead
;; enhance on  your own without needing menus to maintain it!
(Or customize-decompile, or customize-deobfuscate or whatever.)

bug#38696: "If you edit it by hand, you could mess it up"

[Lars Ingebrigtsen]

積丹尼 Dan Jacobson <jidanni@jidanni.org> writes:

> Let's say the user wants to make the font bigger.
> In emacs he goes into the menu bar and picks "Options" > "Set
> Default Font", makes it bigger, and then chooses "Save Options", which
> pastes some "custom-set" code into his .emacs file
> that even contains a warning "If you edit it by hand, you could mess it up",
> meaning for the rest of his life he should just play it safe and stick
> with the menus.

I think the consensus here was that it's fine the way it is, so I'm
closing this bug report.

-- 
(domestic pets only, the antidote for overdose, milk.)
   bloggy blog: http://lars.ingebrigtsen.no