want my if($object) to evaluate false when count($object) === 0

Question

I made an object that was suposed to represent an array, but with a few methods. So I made it implement the native interfaces: IteratorAggregate and Countable. That way you can foreach and count it. So far so good.

But now I want it to evaluate like an array as well. So, if count($object) is zero, if($object) is suposed to evaluate as false. Is there a Comparable interface or something?

Tomás Juárez · Answer 1 · 2013-03-25T20:59:31.747

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Use type Juggling.

You can assign the expected type of your var.

$object = count ( $object );
$object = (array) $object;

The same way, if you want to assign to your variable some other type, here is list of possible values:

(int)
(bool)
(float)
(string)
(array)
(object)
(unset)
(binary)

Also check this this Comparable interface.

edited Mar 25 '13 at 20:59

answered Mar 25 '13 at 20:17

Tomás Juárez

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haha, would be way better just to implement an `isEmpty` method then. what i'm really trying to do is to make it behave like an array. I have no trouble evaluating it...but thanks for the answer anyway :p – Hugo Mota Mar 25 '13 at 20:23
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Oh, you can use (array) – Tomás Juárez Mar 25 '13 at 20:25
well, it would certainly behave like an array. but would also stop behaving like my object. haha – Hugo Mota Mar 25 '13 at 20:29
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Look again the edited answer. Follow the link of the Comparable interface. – Tomás Juárez Mar 25 '13 at 20:34
nice link! apparently it is to be implemented yet...i guess i'll just let the question resting here for a few days, just in case someone comes up with a nice hack (or more info) :p – Hugo Mota Mar 25 '13 at 20:52
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No problem, we're here to help. – Tomás Juárez Mar 25 '13 at 21:00

score 0 · Accepted Answer · edited May 23 '17 at 12:04

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The documentation shows everything that evaluates to false:

the boolean FALSE itself
the integer 0 (zero)
the float 0.0 (zero)
the empty string, and the string "0"
an array with zero elements
an object with zero member variables (PHP 4 only)
the special type NULL (including unset variables)
SimpleXML objects created from empty tags

As of this list an object will never be considered as false. So the only way is to cast the value of count() to boolean using (bool) if you need to do a strict comparison as pointed out in Tomi Sebastián Juárez's answer.

edited May 23 '17 at 12:04

Community

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answered Mar 25 '13 at 20:24

insertusernamehere

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Well, there's that. But i'm trying to keep an open mind here. Few weeks ago I didn't know one could `foreach` or `count` an object either. Who knows... – Hugo Mota Mar 25 '13 at 20:32

want my if($object) to evaluate false when count($object) === 0

2 Answers2