Difference between php5 and php7

 

Feature	Php7	Php5
Performance	Performance speed is double. Average requests per second are 44 when it is 22 in php5.	Performance is low compared to php7.
Return type	You can declare the return type. Example – public function productName (int $id) : String { return “default”; }	No provision for return type declaration
Exception handling	Major errors have been changed to exceptions making them easier to catch.	To handle fatal errors was a difficult task for developers.
Group use declaration	Using the use of declarations makes the code more readable and compact. use pkg\utility\{ClassA, ClassB, ClassC as C}; Similarly, functions and constants can be declared using group use.	Individual declarations for common namespaces. For example – use pkg\utility\ClassA; use pkg\utility\ClassB; use pkg\utility\ClassC;
Support for 64-bit	Supports 64-bit integers and large files.	It doesn't support 64-bit integer.
Anonymous class	A developer can create an anonymous class for a one-off use, rather than creating a full definition of a class that is required only once in the entire application.	There is no concept of anonymous classes.
Three-way comparison operator (spaceship operator)	This operator <==> can compare greater, less than, equal comparisons at the same time. For example – $value = $age1 <=> $age2;	A lot of operators have to be used for comparison – $value = ($age1 > $age2) ? 'Age1 is greater' : 'Age2 is greater';
Null coalescing operator	This operator ?? returns the value of a variable if available, else returns null. $subject = return $_get[‘subject’]?? Null;	The developer has to write explicit code to return the null value if the value is not available. if (isset ($_get [‘subject’])) { $subject = $_GET [‘subject’]; } else $subject = null;