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* Use default value if a variable is not defined
@ 2012-10-11 16:04 Nathan Neff
  2012-10-12 15:52 ` Ivan Andrus
  0 siblings, 1 reply; 2+ messages in thread
From: Nathan Neff @ 2012-10-11 16:04 UTC (permalink / raw)
  To: emacs-orgmode

Hello,

I'm trying to create a function that will tell org-capture
dynamically where to put the captured item.

I have it almost working -- where I'm getting hung up on is
with basic Emacs lisp.  I want to basically implement this
pseudo code:

IF I have defined a variable called njn/current-q-file then
        (find-file njn/current-q-file)
ELSE
       (find-file ("questions.org")))



However, if I do not define my njn/current-q-file then
I get a "Symbol's value as variable is void" error when Emacs starts up.

How do I test for the existence (and non-nil ness of a variable in Emacs)

Thanks,
--Nate

^ permalink raw reply	[flat|nested] 2+ messages in thread

* Re: Use default value if a variable is not defined
  2012-10-11 16:04 Use default value if a variable is not defined Nathan Neff
@ 2012-10-12 15:52 ` Ivan Andrus
  0 siblings, 0 replies; 2+ messages in thread
From: Ivan Andrus @ 2012-10-12 15:52 UTC (permalink / raw)
  To: Nathan Neff; +Cc: emacs-orgmode

On Oct 11, 2012, at 6:04 PM, Nathan Neff wrote:

> Hello,
> 
> I'm trying to create a function that will tell org-capture
> dynamically where to put the captured item.
> 
> I have it almost working -- where I'm getting hung up on is
> with basic Emacs lisp.  I want to basically implement this
> pseudo code:
> 
> IF I have defined a variable called njn/current-q-file then
>        (find-file njn/current-q-file)
> ELSE
>       (find-file ("questions.org")))
> 
> However, if I do not define my njn/current-q-file then
> I get a "Symbol's value as variable is void" error when Emacs starts up.
> 
> How do I test for the existence (and non-nil ness of a variable in Emacs)


You can use boundp.  So 

    (if (boundp 'njn/current-q-file)
        njn/current-q-file
      "questions.org")

can be used wherever you need it.

-Ivan

^ permalink raw reply	[flat|nested] 2+ messages in thread

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2012-10-11 16:04 Use default value if a variable is not defined Nathan Neff
2012-10-12 15:52 ` Ivan Andrus

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