PHP7 vs PHP5
Why PHP7?
1. Performance
2. Spaceship Operator
3. Return type declaration
4. Null Coalesce Operator
before
if (isset ($_GET [‘name’])) { $name = $_GET [‘name’]; } else $name = null;
now
$name = $_GET [‘name’]?? Null;
5. Less memory allocation
PHP5 occupies more memory for the arrays due to the internal structure of the language. It is improved in PHP7. Lets take a example
To measure memory utilization I am using the following script, which tests the creation of an array with 100000 distinct integers:
$startMemory = memory_get_usage();
$array = range(1, 100000);
echo memory_get_usage() - $startMemory, " bytes\n";
The following table shows the results using PHP 5.6 and PHP 7 on 32bit and 64bit systems:
| 32 bit | 64 bit
------------------------------
PHP 5.6 | 7.37 MiB | 13.97 MiB
------------------------------
PHP 7.0 | 3.00 MiB | 4.00 MiB
Typically hashtables are not explicitly ordered,If you iterate over a PHP array you will get back the elements in the exact order in which they were inserted. This means that PHP’s hashtable implementation has to support an additional mechanism for remembering the order of array elements.