Re: emacs-25 10597c9: Don't use 'find-program'

Re: emacs-25 10597c9: Don't use 'find-program'

[Glenn Morris]

If you use grep, :), you'll see that "find-program" is used in other
files as well (find-dired, check-declare, find-cmd).

(Personally I think renaming it to grep-find-program was a too-literal
adherence to the namespace convention. It is the find program, it just
happened to live in grep.el. Its general usefulness is reflected in the
autoload. Maybe you'd be happier moving it to some find*.el file.)

RE: emacs-25 10597c9: Don't use 'find-program'

[Drew Adams]

> (Personally I think renaming it to grep-find-program was a too-literal
> adherence to the namespace convention. It is the find program, it just
> happened to live in grep.el. Its general usefulness is reflected in the
> autoload. Maybe you'd be happier moving it to some find*.el file.)

+1.  It should be called `find-program', IMO.

If there is really a need for a separate such variable that is
specific to `grep' (in addition to a more general such variable,
for most find-program uses), then _that_ variable could be named
`grep-find-program'.

Re: emacs-25 10597c9: Don't use 'find-program'

[Eli Zaretskii]

> Date: Mon, 11 Apr 2016 15:00:33 -0700 (PDT)
> From: Drew Adams <drew.adams@oracle.com>
> Cc: Eli Zaretskii <eliz@gnu.org>
> 
> > (Personally I think renaming it to grep-find-program was a too-literal
> > adherence to the namespace convention. It is the find program, it just
> > happened to live in grep.el. Its general usefulness is reflected in the
> > autoload. Maybe you'd be happier moving it to some find*.el file.)
> 
> +1.  It should be called `find-program', IMO.
> 
> If there is really a need for a separate such variable that is
> specific to `grep' (in addition to a more general such variable,
> for most find-program uses), then _that_ variable could be named
> `grep-find-program'.

The variable I renamed is specific to grep.el.  That other files use
it is a bug in itself.

Re: emacs-25 10597c9: Don't use 'find-program'

[Eli Zaretskii]

> From: Glenn Morris <rgm@gnu.org>
> Cc: Eli Zaretskii <eliz@gnu.org>
> Date: Mon, 11 Apr 2016 17:56:42 -0400
> 
> 
> If you use grep, :), you'll see that "find-program" is used in other
> files as well (find-dired, check-declare, find-cmd).
> 
> (Personally I think renaming it to grep-find-program was a too-literal
> adherence to the namespace convention. It is the find program, it just
> happened to live in grep.el. Its general usefulness is reflected in the
> autoload. Maybe you'd be happier moving it to some find*.el file.)

check-declare uses find/grep, so I changed it to use
grep-find-program.

I don't know what to do about the other 2 cases.  It is certainly
wrong for them to use the same defcustom as used in grep.el and
related commands.  I think they should be changed to use a separate
defcustom (which could be called find-program ;-).  But I leave this
to whoever cares enough to scratch that itch.

Re: emacs-25 10597c9: Don't use 'find-program'

[Glenn Morris]

Eli Zaretskii wrote:

> wrong for them to use the same defcustom as used in grep.el and
> related commands.  I think they should be changed to use a separate
> defcustom (which could be called find-program ;-).

This doesn't make sense to me. Why do you think the "find" in "grep+find"
might need to be different to "find" in any other usage?

Re: emacs-25 10597c9: Don't use 'find-program'

[Eli Zaretskii]

> From: Glenn Morris <rgm@gnu.org>
> Cc: emacs-devel@gnu.org
> Date: Sat, 16 Apr 2016 13:40:53 -0400
> 
> Eli Zaretskii wrote:
> 
> > wrong for them to use the same defcustom as used in grep.el and
> > related commands.  I think they should be changed to use a separate
> > defcustom (which could be called find-program ;-).
> 
> This doesn't make sense to me. Why do you think the "find" in "grep+find"
> might need to be different to "find" in any other usage?

Because it serves a different purpose, and is required to do different
things.

Re: emacs-25 10597c9: Don't use 'find-program'

[Glenn Morris]

Eli Zaretskii wrote:

>> This doesn't make sense to me. Why do you think the "find" in "grep+find"
>> might need to be different to "find" in any other usage?
>
> Because it serves a different purpose, and is required to do different
> things.

So:
find -exec grep

should use find-grep-program

but
find -exec rhubarb

should use find-program?

Please can you give me an example of when this would make sense.

Re: emacs-25 10597c9: Don't use 'find-program'

[Eli Zaretskii]

> From: Glenn Morris <rgm@gnu.org>
> Cc: emacs-devel@gnu.org
> Date: Sun, 17 Apr 2016 13:15:06 -0400
> 
> So:
> find -exec grep
> 
> should use find-grep-program
> 
> but
> find -exec rhubarb
> 
> should use find-program?

Why are you assuming that any 'find' job would necessarily use -exec?

> Please can you give me an example of when this would make sense.

Did you ever need to customize this variable, on any system?  Because
if you didn't, I'm not sure you will ever be able to understand the
need.  Users of GNU/Linux will never need to use this variable.

But since you asked: you might have 2 versions of 'find' (under
different names), one that is good at invoking programs via -exec, the
other that supports the -print0 action.

Basically, imagine a system with several different ports of 'find',
each port with its own advantages and bugs.

Re: emacs-25 10597c9: Don't use 'find-program'

[Paul Eggert]

Eli Zaretskii wrote:
> you might have 2 versions of 'find' (under
> different names), one that is good at invoking programs via -exec, the
> other that supports the -print0 action.

Is this sort of problem common under MS-Windows? It doesn't sound plausible in 
any GNUish or POSIXish system, where any find that supports -print0 should also 
support -exec.

Re: emacs-25 10597c9: Don't use 'find-program'

[Eli Zaretskii]

> Cc: emacs-devel@gnu.org
> From: Paul Eggert <eggert@cs.ucla.edu>
> Date: Sun, 17 Apr 2016 21:39:42 -0700
> 
> Eli Zaretskii wrote:
> > you might have 2 versions of 'find' (under
> > different names), one that is good at invoking programs via -exec, the
> > other that supports the -print0 action.
> 
> Is this sort of problem common under MS-Windows?

Yes.  Find in particular has all kinds of semi-broken ports lying
around.  It's why I needed to do my own port years ago: the best one
in existence then was abysmally slow.  My port is much faster, and
generally doesn't lose features, but even it has deficiencies: for
example, the inode is always zero, so -inum doesn't work.

> It doesn't sound plausible in any GNUish or POSIXish system, where
> any find that supports -print0 should also support -exec.

Like I said: I don't expect this customization to be of any use for
GNU/Linux users.

Re: emacs-25 10597c9: Don't use 'find-program'

[Glenn Morris]

Eli Zaretskii wrote:

> Why are you assuming that any 'find' job would necessarily use -exec?

I'm not, I'm giving it as an example. You've said that find-dired and
grep have different needs, and both may (or may not) use -exec. I found
it really hard to understand what point you were getting at.

Also eg check-declare-directory simply hard-codes -exec, and you changed
that one.

> Did you ever need to customize this variable, on any system? 

No. find-program was never marked as customizable/user-settable till
very recently, so I suspect very few others did.

Please also note that the Emacs build process simply uses "find"
(which is part of POSIX), with both -exec and -print.

But that changes the issue. You are saying it may not only need to be
customizable (which I don't have an issue with), but that there may need
to be two different versions.

> Basically, imagine a system with several different ports of 'find',
> each port with its own advantages and bugs.

I think a system where you have to think which version of find to invoke
depending on what you want to do is a mis-configured system.
I'd just install GNU find and get on with life.

Please give the eventual two variables informative names and docstrings.
It's going to be hard for people on normal systems to figure out
which to use.

This has nothing to with grep, so I would suggest they not live in the
grep namespace.

(Also, grep-xargs-program should just be called xargs-program again.
Hopefully you don't need two versions. :))

Re: emacs-25 10597c9: Don't use 'find-program'

[Glenn Morris]

PS grep.el may use -exec, or it may use -print and xargs. So you will
have to extend its logic to allow switching between your different
versions of find according to which branch it takes. And presumably
encourage other authors using find similarly to do the same.

"Is your journey really necessary?"

Re: emacs-25 10597c9: Don't use 'find-program'

[Eli Zaretskii]

> From: Glenn Morris <rgm@gnu.org>
> Cc: emacs-devel@gnu.org
> Date: Mon, 18 Apr 2016 12:16:15 -0400
> 
> 
> PS grep.el may use -exec, or it may use -print and xargs. So you will
> have to extend its logic to allow switching between your different
> versions of find according to which branch it takes. And presumably
> encourage other authors using find similarly to do the same.
> 
> "Is your journey really necessary?"

Please trust me that I know what I'm doing in this matter.  No amount
of ridicule will ever be able to overcome the years of experience and
the amount of gray hair I can show as evidence.  Please just drop
this.

Re: emacs-25 10597c9: Don't use 'find-program'

[Glenn Morris]

Glenn Morris wrote:

> I think a system where you have to think which version of find to invoke
> depending on what you want to do is a mis-configured system.
> I'd just install GNU find and get on with life.

Or, write a wrapper script that checks its arguments and dispatches to
the appropriate version. Then I only have to change one place, rather
than every utility that uses "find".

Re: emacs-25 10597c9: Don't use 'find-program'

[Eli Zaretskii]

> From: Glenn Morris <rgm@gnu.org>
> Cc: emacs-devel@gnu.org
> Date: Mon, 18 Apr 2016 12:50:16 -0400
> 
> Or, write a wrapper script that checks its arguments and dispatches to
> the appropriate version.

You assume without checking that such a wrapper is possible.

Please just drop this.

Re: emacs-25 10597c9: Don't use 'find-program'

[Glenn Morris]

I'm sorry if you feel there's excessive resistance this.
From the point of view of users of POSIX (ie, non-MS) systems, such a
situation with find is so weird as to seem nonsensical at first sight.

Please note that find-dired is currently broken on emacs-25 due to your
changes. You need to autoload the non-prefixed aliases too, and you
should change all existing uses to remove the compilation warning you've
added.

Frankly this all seems plain wrong to me, but I'll stop discussing it.

Re: emacs-25 10597c9: Don't use 'find-program'

[Eli Zaretskii]

> From: Glenn Morris <rgm@gnu.org>
> Date: Wed, 20 Apr 2016 15:07:13 -0400
> Cc: emacs-devel@gnu.org
> 
> I'm sorry if you feel there's excessive resistance this.
> >From the point of view of users of POSIX (ie, non-MS) systems, such a
> situation with find is so weird as to seem nonsensical at first sight.
> 
> Please note that find-dired is currently broken on emacs-25 due to your
> changes. You need to autoload the non-prefixed aliases too, and you
> should change all existing uses to remove the compilation warning you've
> added.
> 
> Frankly this all seems plain wrong to me, but I'll stop discussing it.

I'm not the only one with write access to the repository.  If you
think the problems are urgent, then there are better ways of getting
them fixed than to keep badgering me.  And if they aren't urgent, then
please trust me that I don't intend to leave the breakage there more
than it takes for me to have a few free moments.

Re: emacs-25 10597c9: Don't use 'find-program'

[Stefan Monnier]

> I'm not the only one with write access to the repository.  If you
> think the problems are urgent, then there are better ways of getting
> them fixed than to keep badgering me.  And if they aren't urgent, then
> please trust me that I don't intend to leave the breakage there more
> than it takes for me to have a few free moments.

FWIW, I'm also puzzled with the grep-find-program thingy (which I guess
shows me POSIX bias).

Could you give some details about when we need to use potentially various
`find` programs, so that we can try and figure out which `find` should
be used where?  The examples you've mentioned so far don't seem to
correlate 100% with the code.


        Stefan

Re: emacs-25 10597c9: Don't use 'find-program'

[Eli Zaretskii]

> From: Stefan Monnier <monnier@iro.umontreal.ca>
> Date: Wed, 20 Apr 2016 15:30:30 -0400
> 
> Could you give some details about when we need to use potentially various
> `find` programs, so that we can try and figure out which `find` should
> be used where?  The examples you've mentioned so far don't seem to
> correlate 100% with the code.

I already wrote everything I have to say about this, sorry.  I have
nothing else to add.

In retrospect, I regret I ever tried to fix this problem.  This
community becomes less and less pleasant, or maybe it's me.

Re: emacs-25 10597c9: Don't use 'find-program'

[Stefan Monnier]

> I already wrote everything I have to say about this, sorry.  I have
> nothing else to add.

I'm sorry you feel this way.  Clearly, your explanation was not
sufficient for me to understand why you think your solution is a good one.

All I really gathered from it is that there are supposedly corner case
situations where you may have 2 versions of `find` installed, both of
them "POSIXish", but where one doesn't accept -print0 and the other
doesn't accept -exec.

Why does renaming find-program to grep-find-program help in such a situation?

Can there be more such odd situations?

If not, then maybe we should have a `find-for-print0-program` and
a `find-for-exec-program`, both of which default to nil which would mean
"just use the value of `find-program`"?


        Stefan

Re: emacs-25 10597c9: Don't use 'find-program'

[John Wiegley]

I fear we sometimes forget how much of a volunteer effort this project is.

None of us are paid to do this, or have much in the way of an incentive to
stay involved, so whatever effort people expend is precious. Remember: people
trade free-time they could spend elsewhere -- such as hanging out with friends
and family -- to improve our beloved Emacs.

Whether a contributed change is excellent, or appropriate, or even just shy of
disastrous, I entreat everyone to review your tone in the messages you send,
and strive to come across as helpful and encouraging. For many of the old-
timers on this list, a single kind word will pay dividends in reams of code;
whereas easily-sent criticisms may end up depriving us of great things that
will now never be.

This is not a direct response to anyone in particular; just the pangs of my
heart as I watch Eli becoming discouraged over a matter that isn't even
difficult to remedy.

-- 
John Wiegley                  GPG fingerprint = 4710 CF98 AF9B 327B B80F
http://newartisans.com                          60E1 46C4 BD1A 7AC1 4BA2

Re: emacs-25 10597c9: Don't use 'find-program'

[Eli Zaretskii]

> From: Glenn Morris <rgm@gnu.org>
> Cc: emacs-devel@gnu.org
> Date: Mon, 18 Apr 2016 12:10:50 -0400
> 
> Eli Zaretskii wrote:
> 
> > Why are you assuming that any 'find' job would necessarily use -exec?
> 
> I'm not, I'm giving it as an example.

Your example made the issue look absurd because it used -exec in both
cases.

> Also eg check-declare-directory simply hard-codes -exec, and you changed
> that one.

Because it calls grep.

> Please also note that the Emacs build process simply uses "find"
> (which is part of POSIX), with both -exec and -print.

I'm not talking about building Emacs, I'm talking about using it.

> > Basically, imagine a system with several different ports of 'find',
> > each port with its own advantages and bugs.
> 
> I think a system where you have to think which version of find to invoke
> depending on what you want to do is a mis-configured system.
> I'd just install GNU find and get on with life.

GNU Find ports are the broken ones I meant above.

Plus, there's a find.exe on Windows that comes with the OS, and does
something very different.  That in itself is already a reason to
rename GNU Find, at least once.

> (Also, grep-xargs-program should just be called xargs-program again.
> Hopefully you don't need two versions. :))

Actually, xargs ports are even more broken than those of Find.

Re: emacs-25 10597c9: Don't use 'find-program'

[Dmitry Gutov]

On 04/17/2016 08:39 PM, Eli Zaretskii wrote:

> But since you asked: you might have 2 versions of 'find' (under
> different names), one that is good at invoking programs via -exec, the
> other that supports the -print0 action.
>
> Basically, imagine a system with several different ports of 'find',
> each port with its own advantages and bugs.

One way to handle this would be to keep find-program as a user option, 
but add a few specialized ones which would default to the former's value.

Re: emacs-25 10597c9: Don't use 'find-program'

[Eli Zaretskii]

> Cc: emacs-devel@gnu.org
> From: Dmitry Gutov <dgutov@yandex.ru>
> Date: Wed, 20 Apr 2016 22:27:31 +0300
> 
> On 04/17/2016 08:39 PM, Eli Zaretskii wrote:
> 
> > But since you asked: you might have 2 versions of 'find' (under
> > different names), one that is good at invoking programs via -exec, the
> > other that supports the -print0 action.
> >
> > Basically, imagine a system with several different ports of 'find',
> > each port with its own advantages and bugs.
> 
> One way to handle this would be to keep find-program as a user option, 
> but add a few specialized ones which would default to the former's value.

I thought about something like that, but decided that I'm not sure
this is better than having just several independent values.  Then each
option keeps its default value irrespective of the others, and the
user doesn't have to review all of them whenever she changes the value
of find-program.

Does this make sense?

Re: emacs-25 10597c9: Don't use 'find-program'

[Stefan Monnier]

> I thought about something like that, but decided that I'm not sure
> this is better than having just several independent values.  Then each
> option keeps its default value irrespective of the others, and the
> user doesn't have to review all of them whenever she changes the value
> of find-program.
> Does this make sense?

From the POSIX point of view where you'd always want to use the same
value everywhere, having to look for all those vars would rather be
a pity.

If she wants to change it only for grep, then she should just only set
grep-find-program and leave find-program unmodified.


        Stefan

Re: emacs-25 10597c9: Don't use 'find-program'

[Dmitry Gutov]

On 04/20/2016 10:37 PM, Eli Zaretskii wrote:

> I thought about something like that, but decided that I'm not sure
> this is better than having just several independent values.  Then each
> option keeps its default value irrespective of the others, and the
> user doesn't have to review all of them whenever she changes the value
> of find-program.
>
> Does this make sense?

If you don't expect anybody to want to customize all (or most) of them 
to the same non-default value, yes.

Otherwise, I agree with Stefan.