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  1. 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
    

    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);
    

    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
    

    $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 the next version of PHP, I would say PHP 5.6 has covered a shipped with a solid amount of improvements and feature additions and it offers one of the easiest upgrades from past versions.

    Don't forget to let us know of any questions or comments you may have in the feed below.

     

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