[PHP] how to pass true/false or "no argument"

2001-10-29 Thread John A. Grant 

I've written several functions with optional "string" parameters.
They work fine. But I've never written one that accepts an optional
"bool" parameter and I'm now confused.

I would like to have this:
somefunction("hello");
somefunction("hello",false);
somefunction("hello",true);

function somefunction($text,$xxx="")
{
if($xxx){
$xxx parameter was passed as true or false
}else{
$xxx parameter was not passed
}
}

Which is correct for the default initialization of $xxx:
$xxx=false;
$xxx=null;
$xxx="";

How do I distinguish between false and "$xxx parameter not
passed"? Do I use isset()? Do I use ===?

Thanks.

--
John A. Grant  * I speak only for myself *  (remove 'z' to reply)
Radiation Geophysics, Geological Survey of Canada, Ottawa
If you followup, please do NOT e-mail me a copy: I will read it here




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Re: [PHP] how to pass true/false or "no argument"

2001-10-29 Thread Henrik Hudson 

If $xxx isn't defined at all, its default is NULL, so your if statement 
should work as is. If $xxx is not defined, then you should get thrown down to 
the else. There is a difference between false and NULL.

On Monday 29 October 2001 10:50, John A. Grant wrote:
>  I've written several functions with optional "string" parameters.
>  They work fine. But I've never written one that accepts an optional
>  "bool" parameter and I'm now confused.
>
>  I would like to have this:
>  somefunction("hello");
>  somefunction("hello",false);
>  somefunction("hello",true);
>
>  function somefunction($text,$xxx="")
>  {
>  if($xxx){
>  $xxx parameter was passed as true or false
>  }else{
>  $xxx parameter was not passed
>  }
>  }
>
>  Which is correct for the default initialization of $xxx:
>  $xxx=false;
>  $xxx=null;
>  $xxx="";
>
>  How do I distinguish between false and "$xxx parameter not
>  passed"? Do I use isset()? Do I use ===?
>
>  Thanks.

-- 

Henrik Hudson
[EMAIL PROTECTED]


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