Where to and why to use empty()

[bunder5]

I don't get the logic behind the construct.  I can't ever see myself using this because it doesn't make sense when I code it. 

 

I understand isset($var) and why I should use it sometimes to avoid undefined messages.

 

But with empty() it makes more sense to always test the variable directly because if the value is NULL, 0, '', or false then it evaluates as TRUE.  Is there any situation where empty should be used always?

 

 

[phporcaffeine]

I don't get the logic behind the construct.  I can't ever see myself using this because it doesn't make sense when I code it. 

 

I understand isset($var) and why I should use it sometimes to avoid undefined messages.

 

But with empty() it makes more sense to always test the variable directly because if the value is NULL, 0, '', or false then it evaluates as TRUE.  Is there any situation where empty should be used always?

 

 

 

empty() is an attempt to simplify things. The function itself, checks for the empty or zero value of string, int and array types. It will return true for everything empty or of zero value, false for anything else.

 

Using empty is great because the name is intuitive when your reading large amounts of code and it's pretty universal in terms of the data types it works with. I've never had issues with it.

 

That said, empty() is the sort of function that loves to get deprecated by language maintainers (not that I have gotten that impression from PHP). Using empty sort of puts all your eggs in one basket; if something happens to empty(), it affects a lot of code. Conversely, if you practice implicit comparisons $a === 0, $a == "" ... etc, then you'll never be affected by baked-in function deprecation.

 

Its tomato tamato; one of the things PHP is famous for is having 18 ways to do a single task, its also a big detractor

 

Some Examples:

$a = array()
count($a) //would return 0
empty($a) //would return true

$a = 0
$b = "0"
empty($a) //would return true
empty($b) //would return true

 

Here is the PHP manual entry for empty(): http://us3.php.net/empty

[bunder5]

Thanks, I understand it better now.