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* How to write specify default values for function arguments?
@ 2002-10-01 18:45 gnuist006
  2002-10-01 20:06 ` Tony
  0 siblings, 1 reply; 3+ messages in thread
From: gnuist006 @ 2002-10-01 18:45 UTC (permalink / raw)


I am looking for multiple ways for
specifying default values for function arguments
as you can do in C++.

thanks

^ permalink raw reply	[flat|nested] 3+ messages in thread
* Re: How to write specify default values for function arguments?
  2002-10-01 18:45 How to write specify default values for function arguments? gnuist006
@ 2002-10-01 20:06 ` Tony
  2002-10-01 23:37   ` Kevin Rodgers
  0 siblings, 1 reply; 3+ messages in thread
From: Tony @ 2002-10-01 20:06 UTC (permalink / raw)


"gnuist006" <gnuist006@hotmail.com> wrote in message
news:b00bb831.0210011045.5f29a1b4@posting.google.com...
> I am looking for multiple ways for
> specifying default values for function arguments
> as you can do in C++.
>
> thanks

use &optional, any parameters left out will be nil.

(defun foo (required-arg &optional opt1 opt2)
 (unless opt1 (setq opt1 default-val-1))
 (unless opt2 (setq opt2 default-val-2))
 ...)

-Tony

^ permalink raw reply	[flat|nested] 3+ messages in thread
* Re: How to write specify default values for function arguments?
  2002-10-01 20:06 ` Tony
@ 2002-10-01 23:37   ` Kevin Rodgers
  0 siblings, 0 replies; 3+ messages in thread
From: Kevin Rodgers @ 2002-10-01 23:37 UTC (permalink / raw)


Tony wrote:

> "gnuist006" <gnuist006@hotmail.com> wrote in message
> news:b00bb831.0210011045.5f29a1b4@posting.google.com...
> 
>>I am looking for multiple ways for
>>specifying default values for function arguments
>>as you can do in C++.
>>
>>thanks
>>
> 
> use &optional, any parameters left out will be nil.
> 
> (defun foo (required-arg &optional opt1 opt2)
>  (unless opt1 (setq opt1 default-val-1))
>  (unless opt2 (setq opt2 default-val-2))
>  ...)


Or do it the Common Lisp way: 


(require 'cl)

(defun* foo (required-arg &optional (opt1 default-val-1) (opt2 default-val-2))
  ...)


-- 
<a href="mailto:&lt;kevinr&#64;ihs.com&gt;">Kevin Rodgers</a>

^ permalink raw reply	[flat|nested] 3+ messages in thread
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2002-10-01 18:45 How to write specify default values for function arguments? gnuist006
2002-10-01 20:06 ` Tony
2002-10-01 23:37   ` Kevin Rodgers

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