PHP 5.6: What’s New
It’s been a long time coming, but we finally have a new version of PHP. With it comes a some nice, new features, improvements to existing features, as well as features that have been removed or marked as deprecated.
Let’s dive in and take a look at everything that’s offered by the latest version.
Backward Incompatible Changes
In this part, I’ll be listing backwards incompatible changes; however, most of your PHP5 code will work in PHP 5.6 without any modifications.
json_decode
As per the JSON specification json_decode()
will immediately eliminate all non-lowercase variants of the JSON literals like true, false and null along with this it will set json_last_error()
accordingly.
GMP Resources
If you are not sure what GMP in PHP then I would advise looking at here. In PHP 5.6, GMP resources are objects. You do not need to make any changes in your existing code unless you are checking resource using explicitly using is_resource()
.
Mcrypt
All Mcrypt function which expect key and IVs will not accept keys or IVs with incorrect size, these functions includes mcrypt_encrypt()
, mcrypt_decrypt()
, mcrypt_cbc()
, mcrypt_cfb()
, mcrypt_ecb()
, mcrypt_generic()
and mcrypt_ofb()
.
Array Values and Overwriting
Before PHP 5.6 when you declare array in class property with explicit and implicit key, array value was overwritten silently when explicit key was the same as a sequential implicit key.
class helloWorld { const ONE = 1; public $array = [ self::ONE => 'Eclipse', 'Sublime', 'PHPStrome', ]; } $hello = new helloWorld(); print_r($hello); // Before PHP 5.6 array('Sublime', 'PHPStrome') // PHP 5.6 array('Eclipse', 'Sublime', 'PHPStrome')
New Features in PHP 5.6
Constant Scalar Expressions
With the release of PHP 5.6, it is possible to provide a scalar expression which includes both numeric and string literals. In previous versions of PHP, it was expected to be static value of constant, function arguments and property declaration.
const ONE = 1; // Scalar Expression in constant const TWO = ONE * 2; class helloWorld { // Scalar Expression in Property const THREE = TWO + 1; // Scalar Expression in Methods public hello f($a = ONE + self::THREE) { return $a; } } echo (new helloWorld)->hello()."\n";
Variadic Functions via “…”
Earlier we were using func_get_args()
to get all arguments available in function call, but with PHP 5.6, this can be removed as we can easily get that facility with ...
operator.
function myTools($name, ...$tools) { echo "Name:". $name.'<br />'; echo "My Tool Count:". count(tools); } myTools('Avinash', 'Eclipse'); // Output: // Name: Avinash // My Tool Count: 1 myTools('Avinash', 'Eclipse', 'Sublime'); // Output: // Name: Avinash // My Tool Count: 2 myTools('Avinash', 'Eclipse', 'Sublime', 'PHPStrom'); // Output: // Name: Avinash // My Tool Count: 3<b> </b>
Argument Unpacking
We can use the same operator (...)
to unpack any argument which is either an array or a set of traversable objects.
function myTools($name, $tool1, $tool2, $tool3) { echo "Name:". $name.'<br />'; echo "Tool1:", $tool1.'<br />'; echo "Tool2:", $tool2.'<br />'; echo "Tool3:", $tool3; } $myTools = ['Eclipse', 'Subline', 'PHPStrom']; myTools('Avinash', ...$myTools); // Output: // Name: Avinash // Tool1: Eclipse // Tool1: Subline // Tool1: PHPStrome
** Shorthand
** operator has been added for exponentiation, we have got support for the shorthand operator as easily.
echo 2 ** 3; echo "<br/>"; $a=2; $a **= 3; echo $a; // Output // 8 // 8
Note that the order of operations comes into play using this operator.
Please take a look at the following example for a clear understanding:
echo 2 ** 2 ** 4;
You might expect it to return 256 as grouping would be like (2 ** 2) ** 4
but that is not the case here.
Real result would be 65536 as grouping would be from right to left and it will parse as 2 ** (2 ** 4)
.
phpdbg
An interactive debugger called phpdbg has been added in PHP 5.6. Please visit the official document for phpdbg.
This phpdbg debugger is implemented as SAPI module.
__debugInfo()
A new magic method added in PHP 5.6, this method allow to change properties and values of an object when the object is output using var_dump()
.
class demoDebugInfo() { private $val; public function __construct($val) { $this->val = $val; } public function __debuginfo() { return [ 'iamchanged' => $this->val + 3; ]; } } $debugInfo = new demoDebugInfo(50); // We will get altered array which is returned by __debuginfo megic method. var_dump($debugInfo);<b> </b>
Default Character Encoding
Default character set for htmlentities()
, html_entity_decode()
and htmlspecialchars()
functions can be set using default_charset()
Large File Upload
It is possible to upload file larger than 2GB.
php://input is reusable
php://input can be used as many times you want to read data. This feature has great reduction in memory compare to reading POST
data.
use function and use const
use
operator has been offered to support extending of constants and functions, this can be performed by using the const
and the use
functions, respectively. Earlier this operator was limited to class only.
Deprecated Features
Call From Incompatible Context
Immediately it will generate E_DEPRECATED
error when you attempt to access non static method statically or static method using object context.
class helloWorld() { public static hiWorld () { } } $hello = new helloWorld(); $hello->hiWorld(); // Before PHP 5.6 E_STRICT error // From PHP 5.6 E_DEPRECATED error<b> </b>
$HTTP_RAW_POST_DATA
$HTTP_RAW_POST_DATA
is deprecated now, we should be using php://input
instead.
Encoding Setting
With the launch of default_charset()
configuration related option is deprecated for iconv
and mbstring
.
List of Changed Functions
List of all changed functions in PHP 5.6 can be found here.
List of New Functions
List of all New functions in PHP 5.6 can be found here.
Conclusion
While the PHP team is working on PHP6, PHP7 and PHPNG, I would say PHP 5.6 has covered a shipped with a solid amount of improvements and feature additions.