RE: An elisp question

RE: An elisp question

[Drew Adams]

> I have a set of `setq' conditions that I wish to group into a 
> function and put inside another function:
> 
> (defun my-test ()
>   (interactive)
>   (if (equal (y-or-n-p "Yes or no? ") t)
>       (setq ps-print-footer t
> 	    ps-print-footer-frame nil
> 	    ps-top-margin 18
> 	    ps-bottom-margin 5
> 	    ps-left-margin 9
> 	    ps-right-margin 7
> 	    ps-print-header nil
> 	    ps-show-n-of-n nil
> 	    ps-print-footer-frame nil
> 	    ps-footer-lines 1
> 	    ps-left-footer (quote ( ))
> 	    ps-footer-offset 0
> 	    )
>     (message "hallo")))
> 
> How can I group all those `setq' conditions into a function 
> and put that function name in place of them in `my-test'
> definition?

(defun foo ()
  (setq ps-print-footer t
	  ps-print-footer-frame nil
	  ps-top-margin 18
	  ps-bottom-margin 5
	  ps-left-margin 9
	  ps-right-margin 7
	  ps-print-header nil
	  ps-show-n-of-n nil
	  ps-print-footer-frame nil
	  ps-footer-lines 1
	  ps-left-footer (quote ( ))
	  ps-footer-offset 0))

(defun my-test ()
  (interactive)
  (if (equal (y-or-n-p "Yes or no? ") t)
      (foo)
    (message "hallo")))

Is this some kind of homework assignment? ;-)

An elisp question

[Rodolfo Medina]

I have a set of `setq' conditions that I wish to group into a function and put
inside another function:

(defun my-test ()
  (interactive)
  (if (equal (y-or-n-p "Yes or no? ") t)
      (setq ps-print-footer t
	    ps-print-footer-frame nil
	    ps-top-margin 18
	    ps-bottom-margin 5
	    ps-left-margin 9
	    ps-right-margin 7
	    ps-print-header nil
	    ps-show-n-of-n nil
	    ps-print-footer-frame nil
	    ps-footer-lines 1
	    ps-left-footer (quote ( ))
	    ps-footer-offset 0
	    )
    (message "hallo")))


How can I group all those `setq' conditions into a function and put that
function name in place of them in `my-test' definition?

Thanks for any help
Rodolfo

Re: An elisp question

[Joost Kremers]

Drew Adams wrote:
> (defun my-test ()
>   (interactive)
>   (if (equal (y-or-n-p "Yes or no? ") t)

(if (y-or-n-p "Yes or no? ")

will do just fine.

>       (foo)
>     (message "hallo")))


-- 
Joost Kremers                                      joostkremers@yahoo.com
Selbst in die Unterwelt dringt durch Spalten Licht
EN:SiS(9)

RE: An elisp question

[Drew Adams]

> > (defun my-test ()
> >   (interactive)
> >   (if (equal (y-or-n-p "Yes or no? ") t)
> 
> (if (y-or-n-p "Yes or no? ")
> 
> will do just fine.
> 
> >       (foo)
> >     (message "hallo")))

Duh. (I didn't try to do more than answer his question.)

Really, the right answer to the OP is to take a look at the manual "Emacs Lisp
Introduction" (aka "An Introduction to Programming in Emacs Lisp") in Info (`C-h
i').

Re: An elisp question

[Oleksandr Gavenko]

Drew Adams пишет:
>>> (defun my-test ()
>>>   (interactive)
>>>   (if (equal (y-or-n-p "Yes or no? ") t)
>> (if (y-or-n-p "Yes or no? ")
>>
>> will do just fine.
>>
>>>       (foo)
>>>     (message "hallo")))
> 
> Duh. (I didn't try to do more than answer his question.)
> 
> Really, the right answer to the OP is to take a look at the manual "Emacs Lisp
> Introduction" (aka "An Introduction to Programming in Emacs Lisp") in Info (`C-h
> i').
> 
Comment please!

In elisp intro (Created on March, 10  2004 by texi2html 1.64)
I not find match of "yes-or-no-p" func and so special example for you say.

In elisp.html (edition 2.8) on "20.6 Yes-or-No Queries" also there no 
special warning about use of "Yes-or-No".

Re: An elisp question

[Joost Kremers]

Oleksandr Gavenko wrote:
> In elisp.html (edition 2.8) on "20.6 Yes-or-No Queries" also there no 
> special warning about use of "Yes-or-No".

the point is that Y-OR-N-P returns either t or nil, so you don't need to
explicitly compare it to T, you can just use it directly as the test for
IF. you wrote:

(if (equal (y-or-n-p "Yes or no? ") t)
    ...

but it's more concise to write:

(if (y-or-n-p "Yes or no? ")
    ...

(btw, if you want to test if a value is t, you can use eq, there's no need
to use equal.)


-- 
Joost Kremers                                      joostkremers@yahoo.com
Selbst in die Unterwelt dringt durch Spalten Licht
EN:SiS(9)

Re: An elisp question

[Bastien]

Oleksandr Gavenko <gavenkoa@gmail.com> writes:

> Comment please!
>
> In elisp intro (Created on March, 10  2004 by texi2html 1.64)
> I not find match of "yes-or-no-p" func and so special example for you say.
>
> In elisp.html (edition 2.8) on "20.6 Yes-or-No Queries" also there no
> special warning about use of "Yes-or-No".

I found this page on EmacsWiki:

http://www.emacswiki.org/cgi-bin/wiki/YesOrNoP

-- 
Bastien

Re: An elisp question

[Nikolaj Schumacher]

Oleksandr Gavenko <gavenkoa@gmail.com> wrote:

> In elisp intro (Created on March, 10  2004 by texi2html 1.64)
> I not find match of "yes-or-no-p" func and so special example for you say.
>
> In elisp.html (edition 2.8) on "20.6 Yes-or-No Queries" also there no special
> warning about use of "Yes-or-No".

I think this is a misunderstanding.  Drew meant the answer on "how to
call a function" was to be found in the elisp intro.  The yes-or-no-p
thing was just an additional note.

Incidentally, if anything, testing for t is more correct.  :) The doc for
`y-or-n-p' clearly states, it will return t for "yes".  It could be
extended to return 'cancel without changing the interface.  Using any
non-nil value as "yes" is indeed an assumption.  (Not that it's likely
to break, or that I haven't made that assumption myself...)


regards,
Nikolaj Schumacher

Re: An elisp question

[Oleksandr Gavenko]

Nikolaj Schumacher пишет:
> 
> Incidentally, if anything, testing for t is more correct.  :) The doc for
> `y-or-n-p' clearly states, it will return t for "yes".  It could be
> extended to return 'cancel without changing the interface.  Using any
> non-nil value as "yes" is indeed an assumption.  (Not that it's likely
> to break, or that I haven't made that assumption myself...)

Thanks, yes for some functions there may by side effect with
non-nil as true!