Setting value 1 when matching two strings

Setting value 1 when matching two strings

[Heime via Users list for the GNU Emacs text editor]

This code sets "isel" to value "1" if "actm" matches "vert". I want to extend this so that value "1"
is also set when "actm" matches "horz".

(let ( (isel (if (equal "vert" actm) 1 -1)) )

Thus when "actm" matches "vert" or "horz", then "isel" has value "1". Otherwise "isel" has value "-1".

Re: Setting value 1 when matching two strings

[Dr Rainer Woitok]

Heime,

On Sunday, 2022-10-16 15:51:44 +0000, you wrote:

> This code sets "isel" to value "1" if "actm" matches "vert". I want to extend this so that value "1"
> is also set when "actm" matches "horz".
> 
> (let ( (isel (if (equal "vert" actm) 1 -1)) )
> 
> Thus when "actm" matches "vert" or "horz", then "isel" has value "1". Otherwise "isel" has value "-1".

In case you don't  really need "vert"  as a string but could as well use
the symbol 'vert,  you could use  "eq" rather than "equal".   And if you
want two or more alternatives, you could use

   (member actm '("vert" "horz"))

or

   (memq actm '(vert horz))

Sincerely,
  Rainer

Re: Setting value 1 when matching two strings

[Heime]

------- Original Message -------
On Sunday, October 16th, 2022 at 4:23 PM, Dr Rainer Woitok <rainer.woitok@gmail.com> wrote:


> Heime,
> 
> On Sunday, 2022-10-16 15:51:44 +0000, you wrote:
> 
> > This code sets "isel" to value "1" if "actm" matches "vert". I want to extend this so that value "1"
> > is also set when "actm" matches "horz".
> > 
> > (let ( (isel (if (equal "vert" actm) 1 -1)) )
> > 
> > Thus when "actm" matches "vert" or "horz", then "isel" has value "1". Otherwise "isel" has value "-1".
> 
> 
> In case you don't really need "vert" as a string but could as well use
> the symbol 'vert, you could use "eq" rather than "equal". And if you
> want two or more alternatives, you could use
> 
> (member actm '("vert" "horz"))
> 
> or
> 
> (memq actm '(vert horz))
> 
> Sincerely,
> Rainer

Am actually using "completing-read".  Thusly, to follow your strategy I have to convert to symbols
after using "completing-read".  What conversion approach would you have in mind?

  (interactive
   (list
    (let ( (cseq '("vert" "partial-disab" "disable" "horz")) )
      (completing-read "icomplt: " cseq nil t "horz"))))

Re: Setting value 1 when matching two strings

[Heime]

------- Original Message -------
On Sunday, October 16th, 2022 at 4:23 PM, Dr Rainer Woitok <rainer.woitok@gmail.com> wrote:


> Heime,
> 
> On Sunday, 2022-10-16 15:51:44 +0000, you wrote:
> 
> > This code sets "isel" to value "1" if "actm" matches "vert". I want to extend this so that value "1"
> > is also set when "actm" matches "horz".
> > 
> > (let ( (isel (if (equal "vert" actm) 1 -1)) )
> > 
> > Thus when "actm" matches "vert" or "horz", then "isel" has value "1". Otherwise "isel" has value "-1".
> 
> In case you don't really need "vert" as a string but could as well use
> the symbol 'vert, you could use "eq" rather than "equal". 

Have seen that with symbols there is no difference between (eq actm 'go) and (equal actm 'go).
Although the recommendation and actual use has always been in support for (eq actm 'go).


> And if you want two or more alternatives, you could use
> 
> (member actm '("vert" "horz"))
> 
> or
> 
> (memq actm '(vert horz))
> 
> Sincerely,
> Rainer

RE: [External] : Re: Setting value 1 when matching two strings

[Drew Adams]

If two objects are `eq' then they are also `equal'.

(`equal' tests with `eq' as the first test it tries.
If that succeeds it returns `t', else it tries other
tests.)

All of this is so clearly explained in the Elisp
manual.  There's really no reason not to consult it.
Even laziness isn't a reason.  Just `i eq RET' takes
you directly to node `Equality Predicates', which
tells you all you need to know, and likely in better
ways than you'll find here.

Which is quicker and easier, `i eq RET' or sending
a mail to help-gnu-emacs@gnu.org and hoping for a
reply that makes sense to you?

Do yourself a favor: Ask Emacs.

RE: [External] : Re: Setting value 1 when matching two strings

[Heime]

------- Original Message -------
On Sunday, October 16th, 2022 at 9:23 PM, Drew Adams <drew.adams@oracle.com> wrote:


> If two objects are `eq' then they are also` equal'.
> 
> (`equal' tests with` eq' as the first test it tries.
> If that succeeds it returns `t', else it tries other tests.) All of this is so clearly explained in the Elisp manual. There's really no reason not to consult it. Even laziness isn't a reason. Just` i eq RET' takes
> you directly to node `Equality Predicates', which tells you all you need to know, and likely in better ways than you'll find here. Which is quicker and easier,` i eq RET' or sending
> a mail to help-gnu-emacs@gnu.org and hoping for a
> reply that makes sense to you?
> 
> Do yourself a favor: Ask Emacs.

I do not know what exactly I have to do to use your suggestion `i eq RET'.
Have been looking at the function documentation with "C-h f" but it is not
very useful from the operational point of view.

Have only started this week and have a month on the task.  Thank you far the guidance.

Re: [External] : Re: Setting value 1 when matching two strings

[Michael Heerdegen]

Heime <heimeborgia@protonmail.com> writes:

> I do not know what exactly I have to do to use your suggestion `i eq RET'.

It's an Info command.

Michael.

Re: [External] : Re: Setting value 1 when matching two strings

[Heime]

------- Original Message -------
On Sunday, October 16th, 2022 at 11:16 PM, Michael Heerdegen <michael_heerdegen@web.de> wrote:


> Heime heimeborgia@protonmail.com writes:
> 
> > I do not know what exactly I have to do to use your suggestion `i eq RET'.
> 
> 
> It's an Info command.
> 
> Michael.

You always fall short of giving enough information to use it.  It is not amusing 
at all.  Pathetic.

Re: [External] : Re: Setting value 1 when matching two strings

[Michael Heerdegen]

Heime <heimeborgia@protonmail.com> writes:

> You always fall short of giving enough information to use it.  It is
> not amusing at all.  Pathetic.

You really did not yet even have one single look into the manual?

You open the GNU Emacs Lisp Reference Manual in the Gnu Emacs info
viewer, and type i eq RET, key by key, literally.

Do you know how to open that manual?

Michael.

Re: [External] : Re: Setting value 1 when matching two strings

[Heime]

Sent with Proton Mail secure email.

------- Original Message -------
On Sunday, October 16th, 2022 at 11:39 PM, Michael Heerdegen <michael_heerdegen@web.de> wrote:


> Heime heimeborgia@protonmail.com writes:
> 
> > You always fall short of giving enough information to use it. It is
> > not amusing at all. Pathetic.
> 
> 
> You really did not yet even have one single look into the manual?
> 
> You open the GNU Emacs Lisp Reference Manual in the Gnu Emacs info
> viewer, and type i eq RET, key by key, literally.
> 
> Do you know how to open that manual?
> 
> Michael.

Have gone through "An Introduction to Programming in Emacs Lisp" but cannot
assimilate all that.  If there was some condensed article about important tools
for the elisp programmer, and a crash course on how to use them, that would be
very helpful.

What I did was look at the emacs website displaying everything on one web page.
The Gnu Emacs Info Viewer, is that when you type "info" at the shell command 
line?

RE: [External] : Re: Setting value 1 when matching two strings

[Drew Adams]

> What I did was look at the emacs website displaying
> everything on one web page. The Gnu Emacs Info Viewer,
> is that when you type "info" at the shell command line?

I recommend you stay in Emacs and ask Emacs.  All of the
Emacs doc - all of its (and other) manuals are available
in Emacs.

`C-h i' takes you to this wonderful world.  There you'll
find "An Introduction to Programming in Emacs Lisp" and
all the rest.

The external Info viewer you mention is similar, but the
Info inside Emacs is superior - because it's inside
Emacs.  You have all of Emacs and its help system ready
to hand while you use Info inside Emacs.
	

RE: [External] : Re: Setting value 1 when matching two strings

[Drew Adams]

> > `i eq RET' ... Do yourself a favor: Ask Emacs.
> 
> I do not know what exactly I have to do to use
> your suggestion `i eq RET'.  Have been looking
> at the function documentation with "C-h f" but
> it is not very useful from the operational point
> of view.

Menubar menu:

 Help > More Manuals > Emacs Lisp Reference

Or just `C-h i  m  el RET'.

That puts you in the `Emacs Lisp manual'.

Menubar menu:

 Info > Index > Lookup a String

Or just `i'.

Then `eq RET'.

That goes to the first manual node referenced by
the first index entry that matches "eq".

> Have only started this week and have a month
> on the task.  Thank you far the guidance.

You're welcome.
___

You'll also do yourself a favor if you read some
of the Info manual:

 Help > More Manuals > All Other Manuals (Info)

Then `m  in RET'.
Or just `C-h i  m  in RET'.

That puts you in the Info manual, which tells
you how to use Info, the hypertext manuals UI.

The Info menu also gives you some navigation
help etc.

Re: [External] : Re: Setting value 1 when matching two strings

[Michael Heerdegen]

Heime <heimeborgia@protonmail.com> writes:

> Have gone through "An Introduction to Programming in Emacs Lisp" but cannot
> assimilate all that.

That's good.  Nobody can assimilate that all at once.  You can leave out
lots of things that are currently not important to you.

> If there was some condensed article about important tools for the
> elisp programmer, and a crash course on how to use them, that would be
> very helpful.

Dunno if that's possible.  Depends too much on the background of the
reader.  And there is a lot of important stuff to know.  I doubt it fits
in a condensed article, and I doubt even more that you would write good
programs after reading that.  It would be a trap.  The manual is not
that long because the authors were bad, it's full of important things.
If you simplify, no matter where, you'll later regret it.  Waste a lot
of time, and still have to read all of it.

> What I did was look at the emacs website displaying everything on one
> web page.  The Gnu Emacs Info Viewer, is that when you type "info" at
> the shell command line?

The command line program "info" is a reader for the Info documentation
for the command line.  Emacs has its own integrated and very nice Info
reader: type C-h i.

Oh, now I see that you only read the introduction, not the Elisp
reference manual.  I suggest to have a look at that one, too.

Yeah sorry if we sometimes sound rude, but all shortcuts are traps,
_all_ - sorry.  It's hard to defer what one actually wants to do and
read that boring stuff instead.  I guess all of us tried some shortcuts.
We all wasted lots of time more or less.

Michael.

Re: [External] : Re: Setting value 1 when matching two strings

[Michael Heerdegen]

Drew Adams <drew.adams@oracle.com> writes:

> `C-h i' takes you to this wonderful world.

I am _very_ thankful that you introduce an optimistic view point.
It is actually fun to browse the Info pages and have such a cool tool
available also for browsing documentation of other programs.

Michael.

RE: [External] : Re: Setting value 1 when matching two strings

[Drew Adams]

> It is actually fun to browse the Info pages and have such a cool
> tool available also for browsing documentation of other programs.

Fun it is.

Other UIs should let you navigate etc. like Info does.
That's sorely missed by anyone used who's been blessed
by Info.

Some UIs have a similar structure - decades after it
was provided in Info (standalone & Emacs).  But they
generally don't let you get around using the keyboard.

Re: [External] : Re: Setting value 1 when matching two strings

[Christopher Dimech]

> Sent: Monday, October 17, 2022 at 12:42 PM
> From: "Michael Heerdegen" <michael_heerdegen@web.de>
> To: help-gnu-emacs@gnu.org
> Subject: Re: [External] : Re: Setting value 1 when matching two strings
>
> Heime <heimeborgia@protonmail.com> writes:
>
> > Have gone through "An Introduction to Programming in Emacs Lisp" but cannot
> > assimilate all that.
>
> That's good.  Nobody can assimilate that all at once.  You can leave out
> lots of things that are currently not important to you.
>
> > If there was some condensed article about important tools for the
> > elisp programmer, and a crash course on how to use them, that would be
> > very helpful.
>
> Dunno if that's possible.  Depends too much on the background of the
> reader.  And there is a lot of important stuff to know.  I doubt it fits
> in a condensed article, and I doubt even more that you would write good
> programs after reading that.  It would be a trap.  The manual is not
> that long because the authors were bad, it's full of important things.
> If you simplify, no matter where, you'll later regret it.  Waste a lot
> of time, and still have to read all of it.

You are quite correct.  What is needed is a tool that gives you a collection
of possible traverses of the manual for what you need, then goes on organising
them for you, and displays them.  That would be the next emacs breakthrough.

In many of the national labs, people don't bother organising things anymore.
It will take more than a lifetime.  Rather it is automated tools that traverse
through all that.  The problem is that one will miss a lot of things nevertheless.
So it is simply a matter of luck.  Have found very few people willing to take the
time to understand the fundamental parts.

> > What I did was look at the emacs website displaying everything on one
> > web page.  The Gnu Emacs Info Viewer, is that when you type "info" at
> > the shell command line?
>
> The command line program "info" is a reader for the Info documentation
> for the command line.  Emacs has its own integrated and very nice Info
> reader: type C-h i.
>
> Oh, now I see that you only read the introduction, not the Elisp
> reference manual.  I suggest to have a look at that one, too.
>
> Yeah sorry if we sometimes sound rude, but all shortcuts are traps,
> _all_ - sorry.  It's hard to defer what one actually wants to do and
> read that boring stuff instead.  I guess all of us tried some shortcuts.
> We all wasted lots of time more or less.
>
> Michael.

Re: [External] : Re: Setting value 1 when matching two strings

[Michael Heerdegen]

Christopher Dimech <dimech@gmx.com> writes:

> You are quite correct.  What is needed is a tool that gives you a
> collection of possible traverses of the manual for what you need, then
> goes on organising them for you, and displays them.  That would be the
> next emacs breakthrough.

All the Emacs info browsing commands and possibilities already help a
bit doing that manually, though.  The Elisp reference manual is a
reference, first and foremost.  As that, discoverability of what is
offered in it is quite good.

Michael.

Re: [External] : Re: Setting value 1 when matching two strings

[Heime]

------- Original Message -------
On Monday, October 17th, 2022 at 12:42 AM, Michael Heerdegen <michael_heerdegen@web.de> wrote:


> Heime heimeborgia@protonmail.com writes:
> 
> > Have gone through "An Introduction to Programming in Emacs Lisp" but cannot
> > assimilate all that.
> 
> 
> That's good. Nobody can assimilate that all at once. You can leave out
> lots of things that are currently not important to you.
> 
> > If there was some condensed article about important tools for the
> > elisp programmer, and a crash course on how to use them, that would be
> > very helpful.
> 
> 
> Dunno if that's possible. Depends too much on the background of the
> reader. And there is a lot of important stuff to know. I doubt it fits
> in a condensed article, and I doubt even more that you would write good
> programs after reading that. It would be a trap. The manual is not
> that long because the authors were bad, it's full of important things.
> If you simplify, no matter where, you'll later regret it. Waste a lot
> of time, and still have to read all of it.
> 
> > What I did was look at the emacs website displaying everything on one
> > web page. The Gnu Emacs Info Viewer, is that when you type "info" at
> > the shell command line?
> 
> 
> The command line program "info" is a reader for the Info documentation
> for the command line. Emacs has its own integrated and very nice Info
> reader: type C-h i.
> 
> Oh, now I see that you only read the introduction, not the Elisp
> reference manual. I suggest to have a look at that one, too.
> 
> Yeah sorry if we sometimes sound rude, but all shortcuts are traps,
> all - sorry. It's hard to defer what one actually wants to do and
> read that boring stuff instead. I guess all of us tried some shortcuts.
> We all wasted lots of time more or less.
> 
> Michael.

I am an impatient person, and in the habit of running doing a job,  
which can blow people's fuses.  Great that things have settled down
now.

Re: [External] : Re: Setting value 1 when matching two strings

[Jean Louis]

* Heime <heimeborgia@protonmail.com> [2022-10-17 01:37]:
> > Do yourself a favor: Ask Emacs.
> 
> I do not know what exactly I have to do to use your suggestion `i eq RET'.
> Have been looking at the function documentation with "C-h f" but it is not
> very useful from the operational point of view.
> 
> Have only started this week and have a month on the task.  Thank you far the guidance.

While keep asking Emacs feel free to keep asking here. Mailing list is
for human interaction, as Emacs has no idea (when you are asking it)
if you understood the information or not.

But we do.

-- 
Jean

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