The PHP development team announced new release of PHP 5.6. The new release brings new features and lots of improvements, development team say, also as some backward incompatible changes.
Following are the most important changes in PHP 5.6 release:
Constant scalar expressions
It is now possible to provide a scalar expression involving numeric and string literals and/or constants in contexts where PHP previously expected a static value, such as constant and property declarations and default function arguments.
<?php
/*
Online PHP Examples with Source Code
website: http://4evertutorials.blogspot.com/
*/
const ONE = 1;
const TWO = ONE * 2;
class C {
const THREE = TWO + 1;
const ONE_THIRD = ONE / self::THREE;
const SENTENCE = 'The value of THREE is '.self::THREE;
public function f($a = ONE + self::THREE) {
return $a;
}
}
echo (new C)->f()."\n";
echo C::SENTENCE;
//The above example will output:
/*
4
The value of THREE is 3
*/
?>
Improved syntax for variadic functions
Variadic functions can be declared through a new ... operator:
<?php
/*
Online PHP Examples with Source Code
website: http://4evertutorials.blogspot.com/
*/
function f($req, $opt = null, ...$params) {
// $params is an array containing the remaining arguments.
printf('$req: %d; $opt: %d; number of params: %d'."\n",
$req, $opt, count($params));
}
f(1);
f(1, 2);
f(1, 2, 3);
f(1, 2, 3, 4);
f(1, 2, 3, 4, 5);
// The above example will output:
/*
$req: 1; $opt: 0; number of params: 0
$req: 1; $opt: 2; number of params: 0
$req: 1; $opt: 2; number of params: 1
$req: 1; $opt: 2; number of params: 2
$req: 1; $opt: 2; number of params: 3
*/
?>
Argument unpacking via ... operator
Arrays and Traversable objects can be unpacked into argument lists when calling functions by using the ... operator. This is also known as the splat operator in other languages, including Ruby.
<?php
/*
Online PHP Examples with Source Code
website: http://4evertutorials.blogspot.com/
*/
function add($a, $b, $c) {
return $a + $b + $c;
}
$operators = [2, 3];
echo add(1, ...$operators);
// The above example will output:
/*
6
*/
?>
Exponentiation via ** operator
A right associative ** operator has been added to support exponentiation, along with a **= shorthand assignment operator.
<?php
/*
Online PHP Examples with Source Code
website: http://4evertutorials.blogspot.com/
*/
printf("2 ** 3 == %d\n", 2 ** 3);
printf("2 ** 3 ** 2 == %d\n", 2 ** 3 ** 2);
$a = 2;
$a **= 3;
printf("a == %d\n", $a);
// The above example will output:
/*
2 ** 3 == 8
2 ** 3 ** 2 == 512
a == 8
*/
?>
use function and use const
The use operator has been extended to support importing functions and constants in addition to classes. This is achieved via the use function and use const constructs, respectively.
<?php
/*
Online PHP Examples with Source Code
website: http://4evertutorials.blogspot.com/
*/
namespace Name\Space {
const FOO = 42;
function f() { echo __FUNCTION__."\n"; }
}
namespace {
use const Name\Space\FOO;
use function Name\Space\f;
echo FOO."\n";
f();
}
// The above example will output:
/*
42
Name\Space\f
*/
?>
Now UTF-8 is Default character encoding
default_charset is now used as the default character set for the htmlentities(), html_entity_decode() and htmlspecialchars() functions. Note that if the (now deprecated) iconv and mbstring encoding settings are set, they will take precedence over default_charset for iconv and mbstring functions, respectively.
Large file uploads
Files larger than 2 gigabytes in size are now accepted.
GMP supports operator overloading
GMP objects now support operator overloading and casting to scalar types. This allows for more expressive code using GMP:
<?php /* Online PHP Examples with Source Code website: http://4evertutorials.blogspot.com/ */ $a = gmp_init(42); $b = gmp_init(17); // Pre-5.6 code: var_dump(gmp_add($a, $b)); var_dump(gmp_add($a, 17)); var_dump(gmp_add(42, $b)); // New code: var_dump($a + $b); var_dump($a + 17); var_dump(42 + $b); ?>
Full list of all changes in PHP 5.6 can be additionally found in the here.
