[php[world] 2014] PHP 5.NEW: The Best Bits

PHP 5.NEW
The Best Bits

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Proprietary and Confidential
•Community Engineer at Engine
Yard
•Author of Zend PHP 5
Certification Study Guide,
Sitepoints PHP Anthology: 101
Essential Tips, Tricks & Hacks &
PHP Master: Write Cutting Edge
Code
•A contributor to Zend Framework
1 & 2, phpdoc, & PHP internals
• Original creator of PHAR/
PHP_Archive
• Lead for PHPWomen US
•@dshafik
Davey Shafik

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$30
(Includes Taxes & Shipping)

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Let’s start a conversation about
mental health in tech
prompt.engineyard.com

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About These Slides

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Two slides per “slide”
Title Slide (for when I’m talking)
Details slide (for later)
Nobody likes it when you can read the slide just as well as the speaker
can
I like slides that are useful
About These Slides

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Version Indicator:
5.X

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Version Indicator:
5.X
5.X
+
Multiple Versions

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The Small Stuff

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PHP 5.3
Release Date: June 30th 2009 (5-15% Faster)
5.3

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• Extensions:
• ereg deprecated
• SPL always enabled
• Reflection always enabled
• NOWDOC
• Goto
• stream_context_set_default()
• Magic Methods:
• __invoke()
• __callStatic()
• __call() now called on protected/private method access
• Performance Increase!
PHP 5.3
5.3

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PHP 5.4
Release Date: March 1st 2012 (10-15% Faster)
5.4

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• SessionHandlerInterface added, used with
session_set_save_handler()
• PHP_BINARY constant gives the path to the... PHP binary
• Notice now shown on array-to-string conversions
• UTF-8 by default (instead of iso-8859-1)
• Array callbacks — $foo = [$obj, ‘method’]; $foo =
[“Class”, “method”]; then: $foo();
• Callable typehint, accepts function names, array callbacks, closures,
classes with __invoke() magic method
• Better Memory Usage and Performance
• (even better than PHP 5.3)
PHP 5.4
5.4

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PHP 5.5
Release Date: June 20th 2013
5.5

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• PCRE /e Modifier deprecated
• ext/mysql now officially deprecated
• boolval() to complement intval(), floatval()/doubleval(),
strval(). Same as (bool) $var;
• JsonSerializable interface
• Fully-qualified Class name constant: ClassName::CLASS
• empty() now supports any valid expression
• set_(error|exception)_handler() to NULL to return to default
behavior
PHP 5.5
5.5

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PHP 5.6
Release Date: August 28th 2014
5.6

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• T_POW: ** Exponent operator, raise left operand to the power of right
• Constant Scalar Expressions
• __debugInfo() magic method — intercept var_dump()
• GMP operator overloading (engine level only
!)
PHP 5.6
5.6

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Namespaces
Better Code Organization
5.3
5.6
+

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• Avoid Naming Collisions
• Alias Long Names
• Must be defined at the top
• Relative Namespaces are Supported
• Import/Alias with "use" keyword
• Can namespace classes, functions, and constants (using const)
Namespaces
namespace Zend\Http\Client\Adapter;
class Socket implements HttpAdapter, StreamInterface
{
}
?>
5.3

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Namespaces
namespace Zend;
use Zend\Http\Client\Adapter\Socket as HttpClient;
$client = new Http\Client\Adapter\Socket;
$client = new HttpClient;
$client = new Zend\Http\Client\Adapter\Socket;
?>
5.3

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PSR-0
A new standard
5.3

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http://xkcd.com/927/
5.3

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• Remove leading namespace separator
• Replace namespace separator with directory separator
• Replace underscores with directory separator
• Add .php to the end
PSR-0
5.3

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namespace Zend\Http\Client\Adapter;
class Socket implements HttpAdapter, StreamInterface
{
}
?>
PSR-0
5.3

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Composer
getcomposer.org
5.3

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Composer
composer.json:
{
"require": {
"monolog/monolog": "1.2.*",
"phpunit/phpunit": "3.*",
"zend/zendframework": ">=2.0, < 3.0",
"zend/zendframework": "~2.0"
}
}
5.3

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Install dependencies (from composer.lock)
$ composer install
Update dependencies & write composer.lock
$ composer update
Composer
5.3

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require 'vendor/autoload.php';
use Zend\Http\Client\Adapter\Socket as HttpClient;
$client = new HttpClient;  
// Automagically (lazy) loaded
Optimize the Autoloader with a classmap:
$ composer install --optimize-autoloader
$ composer update --optimize-autoloader
Autoloading
5.3

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Import Namespaced Functions & Constants
5.6

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• Prior to PHP 5.6:
• Outside of the namespace, function names/constants had to be fully
qualified
• You could alias the namespace to shorten it (ugh!)
• Add two new keyword sequences:
• use function \foo\bar\function
• use const \foo\bar\BAZ
• Use commas to import multiples
5.6

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namespace foo\bar {
const HELLO_WORLD = "Hello World";
function strlen($str) {
return \strlen($str);
}
}
namespace {
use function foo\bar\strlen;
use function foo\bar\non_existent; // Doesn't exist!
use const foo\bar\HELLO_WORLD;
var_dump(strlen(HELLO_WORLD)); // not ambiguous
var_dump(non_existent()); // Does not fall-through
// to global scope: fatal error
}
5.6

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Great for DSLs!
use function html\div, html\p, html\em;
$html = div(p('Some', em('Text')));
5.6

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Closures
5.3
5.4
+

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Closures
$a = array(3, 2, 5, 6, 1);
usort($a, function ($a, $b) {
if ($a == $b) {
return 0;
}
return ($a < $b) ? -1 : 1;
});
?>
5.3

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• Explicitly passed in via the use construct
Inheriting Scope
$who = "World";
$sayHello = function() use ($who) {
echo "Hello $who";
};
$sayHello();
5.3

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• $this now accessible inside closures (based on creation location)
• Array callbacks for variable function calls
• Change $this and/or scope with Closure::bind() and  
Closure->bindTo()
$this in closures
5.4

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class foo {
public function getClosure() {
return function() {  
return $this;
}
}
}
class bar {
public function __construct() {
$foo = new foo();
$func = $foo->getClosure();
$obj = $func();  
// PHP 5.3: $obj == null
// PHP 5.4: $obj == foo, not bar
}
}
5.4

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Rebinding $this
Or: How to break the object model!
5.4

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• Doesn’t change the original closure — creates a duplicate
• $this can be any object
• $this and scope are separate — $this can be a different class to the
access scope.
Rebinding $this
5.4

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Rebinding $this
class foo {
return function() {
echo $this->hello;
$this->world();
};
}
}
class bar {
public $hello = "Hello ";
private function world() { echo "World"; }
}
$foo = new Foo();
$closure = $foo->getClosure();
$bar = new Bar();
$newClosure = $closure->bindTo($bar);
$newClosure();
5.4

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Hello
Fatal error: Call to private method
bar::world() from context 'foo'
Output
5.4

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Rebinding $this
class foo {
return function() {
echo $this->hello;
$this->world();
};
}
}
class bar {
public $hello = "Hello ";
}
$foo = new Foo();
$closure = $foo->getClosure(); 
$bar = new Bar();
$newClosure = $closure->bindTo($bar);
$newClosure = $closure->bindTo($bar, $bar);
$newClosure(); // Hello World
5.4

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Dereferencing
5.4
5.5
+

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Array Dereferencing
function returnArray() {
return ['a' => 'b', 'c' => 'd'];
}
$foo = returnArray()['a']; // b
5.4
5.5
Literal Dereferencing
["one", "two", "three"][0]; // "one"
"foo"[0]; // f

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Traits
AKA Horizontal Re-use
5.4

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• Compiler-level copy and paste (almost literally!)
• New Keywords: trait, use, as and insteadof
• Can use multiple traits
– as and insteadof resolve conflicts
• Can define methods, abstract methods, and properties
• Can be namespaced, identified just like classes/functions/constants
Traits
5.4

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namespace Ds\Util;
trait SecureDebugInfo {
public function __debugInfo() {
$info = (array) $this;
foreach ($info as $key => $value) {
// Hide elements starting with '_'
if ($key[0] == '_') {
unset($info[$key]);
}
}
}
}
Defining a Trait
5.4

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• Uses the “use” keyword
• Use multiple traits like namespaces, separate use calls, or comma-
separated.
Using a Trait
namespace Ds;
class MyClass {
use Util\SecureDebugInfo;
}
5.4

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trait One {
public function one() { }
}
trait Two {
public function two() { }
}
trait Three {
use One, Two; // Trait three now comprises of  
// all three traits.
public function Three() { }
}
Inheriting In Traits
5.4

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class Numbers {
use One; // Adds One->one()
public function two() { }
public function three() { }
}
class MoreNumbers extends Numbers {
use Two; // Two->two() overrides Numbers->two()
public function one() { } // Overrides Numbers->one()
} (Trait One->one)
class EvenMoreNumbers extends MoreNumbers {
use Three; // Three->one() overrides MoreNumbers->one()
// Three->two() overrides MoreNumbers->two()  
// (Trait Two->two)
// Three->three() overrides inherited  
Numbers->three()
public function three() { } // Overrides Three->three()
}
Inheritance & Traits 5.4

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namespace Ds\Util;
trait SecureDebugInfo {
public function __debugInfo()
{
return $this->getData();
}
abstract public function getData();
}
Trait Requirements
5.4

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Fatal error: Trait method has not been
applied, because there are collisions with other
trait methods on
class MyClass {
use Ds\Util\SecureDebugInfo,  
My\Framework\DebugHelper {
Ds\Util\SecureDebugInfo::__debugInfo
insteadof My\Framework\DebugHelper;
}
}
Conflict Resolution
5.4

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class MyClass {
use Ds\Util\SecureDebugInfo,
My\Framework\DebugHelper {
Ds\Util\SecureDebugInfo::__debugInfo
insteadof My\Framework\DebugHelper;
My\Framework\DebugHelper::__debugInfo
as debugHelperInfo;
}
}
Aliases
5.4

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class MyClass {
use MyTrait {
MyTrait::myMethod as protected;
MyTrait::myOtherMethod as private AliasName;
}
}
Changing Visibility
5.4

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class Numbers {
use One, Two;
}
var_dump(class_uses('Numbers'));
Output:
array(2) {
["One"]=>
string(3) "One"
["Two"]=>
string(3) "Two"
}
Using Array Dereferencing:
if (class_uses('MyClass')['SomeTrait']) {
// MyClass uses the SomeTrait
}
Detecting Traits
5.4

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trait sayHello {
public function hello() { echo "Hello "; }
}
trait sayWorld {
public function world() { echo "World"; }
}
class sayHelloWorld {
use sayHello, sayWorld;
}
$say = new sayHelloWorld();
$say->hello(); // Hello
$say->world(); // World
Traits

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trait getHello {
public function hello() { return "Hello"; }
}
trait getWorld {
public function world() { return "World"; }
}
trait sayHelloWorld {
use getHello, getWorld;
public function helloWorld() {
echo $this->hello(), " ", $this->world();
}
}
class Greeting {
use sayHelloWorld;
}
(new Greeting)->helloWorld(); // Hello World
Inheritance/Scope

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class say {
public function sayHello() {
echo 'Hello ';
}
}
trait sayWorld {
parent::sayHello(); // parent is unknown
echo 'World';
}
}
class HelloWorld extends say {
use sayWorld; // parent == say
}
class HiMum extends HelloWorld {
parent::sayHello(); // parent == HelloWorld == sayWorld
echo ", Hi mum!", PHP_EOL;
}
}
(new HelloWorld)->sayHello(); echo PHP_EOL; // Hello World
(new HiMum)->sayHello(); // Hello World, Hi mum!
Precedence

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trait sayHello {
}
trait sayWorld {
}
use sayHello, sayWorld {
world as public;
}
}
$say->hello(); // Hello
$say->world(); // World
Method Visibility

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trait sayHello {
}
trait sayWorld {
}
use sayHello, sayWorld {
hello as greeting;
world as public planet;
}
}
$say->greeting(); // Hello
$say->planet(); // World
Method Aliases

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trait hello_en {
public function greet() { echo "Hello "; }
}
trait mother_en_US {
public function mother() { echo "Mom"; }
}
trait mother_en_UK {
public function mother() { echo "Mum"; }
}
class HiMother {
use hello_en, mother_en_US, mother_en_UK;
public function sayHi($locale = 'UK') {
$this->greet();
($locale != 'US') ? $this->mother() : $this->mom();
}
}
(new HiMother)->sayHi('UK');
(new HiMother)->sayHi('US');
Fatal error: Trait method mother has not been applied, because there are
collisions with other trait methods on HiMother on line 28
Conflicts

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trait hello_en {
public function greet() { echo "Hello "; }
}
trait mother_en_US {
public function mother() { echo "Mom"; }
}
trait mother_en_UK {
public function mother() { echo "Mum"; }
}
class HiMother {
use hello_en, mother_en_US, mother_en_UK {
mother_en_UK::mother insteadof mother_en_US;
mother_en_US::mother as mom;
}
public function sayHi($locale = 'UK') {
$this->greet();
($locale != 'US') ? $this->mother() : $this->mom();
}
}
(new HiMother)->sayHi('UK'); // Hello Mum
(new HiMother)->sayHi('US'); // Hello Mom
Conflict Resolution

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Short Echo Tags
5.4

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No longer depends on short_open_tags
Short Echo Tags
="Now I Will Always Work!";?>
5.4

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Binary Numbers
5.4

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Binary Numbers
$var = 0b01; // Binary (base 2)
In Addition To:
$var = 1234; // Integer
$var = -123; // Signed Integer (+/-)
$var = 1.23; // Float
$var = 0123; // Octal (base 8)
$var = 0x1A; // Hexadecimal (base 16)
5.4

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Short Array Syntax
5.4

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Short Array Syntax
// Old
$array = array(1, 2, 3);
// New
$array = [1, 2, 3];
// Old
$a = array('a' => 'b', 'c' => 'd'); 
// New
$a = ['a' => 'b', 'c' => 'd'];
5.4

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Dynamic Method Calls
5.4

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Dynamic Method Calls
// Variable static methods
$var = "staticMethod";
ClassName::{$var}();
// Instantiation Time Access
(new ClassName)->instanceMethod(); 
 
// UGLY.
$var = "instanceMethod";
(new ClassName)->{$var}();
5.4

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list() support in foreach
5.5

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• Allows assignment of nested array values (1st level) to
multiple variables, within the foreach declaration
list() support in foreach
$result = [
[
'name' => 'Davey Shafik',
'email' => '[email protected]',
],
[
'name' => 'Helgi Þormar Þorbjörnsson',
'email' => '[email protected]',
]
];
foreach ($result as list($name, $email)) {
echo $name, ': ', $email . PHP_EOL;
}
5.5

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Constant Scalar Expressions
5.6

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• Use expressions when defining:
• global constants with const keyword
• class constants with the const keyword
• class properties
• static variables
• function arguments
Constant Scalar Expressions
5.6

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• 123 - Integers
• 123.456 - Floats
• “foo” - Strings
• __LINE__ - Line magic constant
• __FILE__ - File magic constant
• __DIR__ - Directory magic constant
• __TRAIT__ - Trait magic constant
• __METHOD__ - Method magic constant
• __FUNCTION__ - Function magic constant
• __NAMESPACE__ - Namespace magic constant
• <<• <<<'NOWDOC' - NOWDOC string syntax
• SOME_RANDOM_CONSTANT - Constants
Expression Suppport
5.6

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Global constants with const keyword
const FOO = 1 + 1;
const BAR = 1 << 1;
const GREETING = "HELLO";
const BAZ = GREETING." WORLD!"
5.6

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Class constants with the const keyword
class Foo {
const FOO = 1 + 1;
const BAR = 1 << 1;
const GREETING = "HELLO";
const BAZ = self::GREETING." WORLD!"
}
5.6

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Class Properties
class Foo {
const BAZ = 10;
}
class Bar {
public $foo = 1 + 1;
public $bar = [
1 + 1,
1 << 2,
Foo::BAZ => "foo "."bar"
];
public $baseDir = __DIR__ . "/base";
}
5.6

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Static Variables
const BAR = 0x10;
function foo() {
static $a = 1 + 1;
static $b = [1 << 2];
static $c = 0x01 | BAR;
}
5.6

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Function Arguments
const BAR = 1;
function f($a = 1 + 1, $b = 2 << 3, $c = BAR?10:100)
{
}
5.6

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__debugInfo()
5.6

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Magic method to control the output of var_dump()
__debugInfo()
class File {
// "Resource(stream)" isn't all that useful
private $fp;
// But all the stream meta data is
public function __debugInfo() {
return $this->fp ? stream_get_meta_data($fp) : [];
}
public function open($filename, $mode = 'r'){
$this->fp = fopen($filename, $mode);
}
}
5.6

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__debugInfo() (Cont.)
$f = new File;
var_dump($f); // object(File)#1 { }
$f->open('http://php.net');
var_dump($f);
/*
object(File)#1 {
["wrapper_type"]=>
string(4) "http"
["stream_type"]=>
string(10) "tcp_socket"
etc...
*/
5.6

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“finally” keyword
5.5

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• Code within a ﬁnally block is always run after either of the
try, or catch blocks.
• Remember: Catch is optional
“finally” keyword
try {
// Try something
} catch (\Exception $exception) {
// Handle exception
} finally {
// Whatever happened, do this
}
5.5

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Fully Qualified Classname Constant
5.5

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• Easy access to the fully qualiﬁed class name via a simple constant.
Allows for easy dynamic creation of class (think: Reﬂection, Unit
Testing)
Fully Qualified Classname Constant
namespace App {
class Config { }
$className = "Config";
new $className; // Fatal error: Class 'Config' not found
// Instead:
$className = "App\Config";
new $className; // Works
// Added in 5.5:
$className = Config::class; // = App\Config
new $className;
}
5.5

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Simple Password Hashing
5.5

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• Makes password hashing super easy
• Purpose: to make sure everyone uses safe password
storage
• Uses the excellent bcrypt (currently)
• Salting is automatic, but can be supplied
• The hash itself identiﬁes the algorithm, salt and options
options when passed to password_verify()
•You may pass an array with salt and cost as third
argument to password_hash()
Simple Password Hashing
5.5

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Simple Password Hashing (cont.)
$options = [
'cost' => 20,
'salt' => 'bcryptuses22characters'
];
$hash = password_hash("testing", PASSWORD_DEFAULT, $options);
$hash = password_hash("testing", PASSWORD_DEFAULT);
if (password_verify("testing", $hash)) {
// valid
}
Specify Options:
5.5

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• Also provides two helper functions:
–password_needs_rehash() will determine if the hash uses the
current algorithm, cost and salt, returning true if it doesn’t match.
–password_get_info() returns an array providing information about
a hash such as algorithm, cost and salt.
Simple Password Hashing (cont.)
5.5

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More on password security
5.5

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• A strong salt makes a dictionary attack much more difﬁcult
• A high cost means it takes a long time (say, 1/10th second)
to generate a single password, making brute force attacks
too slow to be effective
• The cost is what makes SHA-1 and MD5 poor options
because they are designed to be fast, this is the enemy of
security.
• Additionally, MD5 suffers from too many easy collisions (e.g.
two different strings that create the same hash)
More on password security
Goal: Make both dictionary and brute force attacks difﬁcult.
5.5

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Hashing Rates
Algorithm
Hashes/
second
MD5 SHA-1 SHA-512 bcrypt
MD5
180 Billion/
second
65% Faster
99.9997%
Faster
99.9999996%
Faster
SHA-1
63 Billion/
second
185% Slower
99.9994%
Faster
99.999887%
Faster
SHA-512
364,000/
second
49.5M%
Slower
17.3M%
Slower
80.49%
Faster
bcrypt
71,000/
second
253.5M%
Slower
88.7M%
Slower
412% Slower
Data Source: http://passwords12.at.iﬁ.uio.no/Jeremi_Gosney_Password_Cracking_HPC_Passwords12.pdf
5.5

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Generators
5.5

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• Introduces new yield keyword - execution is handed back
to the iterating mechanism (e.g. foreach) and then continues
from, the yield
• Functions and methods are automatically return generators
when yield is found within them
• Generators are just simple ways to implement iterators;
without having to duplicate a bunch of boilerplate code
• Technically implemented using the Generator class, similar
to the magic Closure class.
Generators
5.5

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Anatomy of Generator Flow
function helloGenerator($who) {
// First iteration starts here
$greeting = ["Hello", "Hi", "Hola", "Bonjour"][rand(0, 3)];
yield $greeting; // Control passed back to foreach
// Next iteration starts here
yield " "; // Control passed back to foreach
// Third iteration starts here
yield ucfirst($who) . "!\n"; // Control passed back to foreach
}
$generator = helloGenerator("world"); // No code is executed yet
foreach ($generator as $value) {
echo $value;
}
Output: $RandomGreeting World!\n
5.5

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Anatomy of Generator Flow (Cont.)
function MyGenerator() {
// First iteration starts here
for ($i = 0; $i < 5; $i++) {
yield $i; // Control passed back to foreach
// Second iteration starts here
// The for iteration completes, and goes to the next loop
}
}
0: 0
1: 5
2: 10
3: 15
4: 20
Output
5.5

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function gen() {
echo "One";
yield "Two";
echo "Three";
yield "Four";
echo "Five";
}
$generator = gen();
$generator->rewind();
if ($generator->valid()) {
echo $generator->current();
}
$generator->next();
5.5

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• A return; (note: a return with a value is a parse error)
• An exception is thrown (and not caught within the generator)
• There are no more yields
Generators will return true for valid() until:
5.5

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Sending Data into a Generator
5.5

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• You can send any data into a generator
• It is used as an expression, rather than a statement
• This also advances the generator
• You can send and receive at the “same time”
Sending data into a Generator
function logger($fileName) {
$fileHandle = fopen($fileName, 'a');
while (true) {
fwrite($fileHandle, yield . PHP_EOL);
}
}
$logger = logger(__DIR__ . '/log');
$logger->send('Foo');
$logger->send('Bar');
5.5

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Confession Time
5.5

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• My ﬁrst implementation for the next slide didn’t work how I
expected!
• Neither did the 2nd, 3rd or 4th...
• In fact, I thought I found a bug
• Then I created a test case, and things started to make
sense
• I still don’t think there’s any reasonable use-case for this
functionality!
Confession Time
5.5

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Test Case
function gen() {
$i = 0;
while (true) {
file_put_contents("./log",
myDate() .' '.
(yield $i++) . ' ' .
PHP_EOL
, FILE_APPEND);
}
}
function myDate() {
return date("Y-m-d H:i:s");
}
$gen = gen();
var_dump($gen->send("First Call")); // 1
sleep(3);
var_dump($gen->send("Second Call")); // 2
Log File
2013-02-04 03:39:51 First Call
2013-02-04 03:39:51 Second Call
5.5

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Iteration 1
5.5

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Iteration 2 5.5

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Sending Exceptions into Generators
5.5

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• Sends an exception into the Generator
• Throws the exception at the yield
• The actual yielded value isn’t returned
5.5

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Variadic Functions
5.6

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Variadic Syntax
… $variable
5.6

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• Variadic means to accept a variable number of arguments
• Previously you needed to use func_num_args()/func_get_args()
• Which includes defined arguments also!
• New syntax: "… $variable" (triple dot)
• Array with just the variable arguments
• Self-documenting code
• Supports by-reference
• Allows type hints
• Must be the last argument!
Variadic Functions
5.6

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Variadic Functions
function fn($reqParam, $optParam = null, ...$params) {
var_dump($reqParam, $optParam, $params);
}
fn(1); // 1, null, []
fn(1, 2); // 1, 2, []
fn(1, 2, 3); // 1, 2, [3]
fn(1, 2, 3, 4); // 1, 2, [3, 4]
fn(1, 2, 3, 4, 5); // 1, 2, [3, 4, 5]
5.6

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Variadic Functions — References
5.6
class MySQL implements DB {
public function prepare($query, &...$params) {
$stmt = $this->pdo->prepare($query);
foreach ($params as $i => &$param) {
$stmt->bindParam($i + 1, $param);
}
return $stmt;
}
// ...
}
$stmt = $db->prepare( 
'INSERT INTO users
(name, email, age)  
VALUES (?, ?, ?)', $name, $email, $age); 
foreach ($usersToInsert as list($name, $email, $age)) {
$stmt->execute();
}

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Variadic Functions — Type hints
function hooks($name, Callable ... $callbacks) {
foreach ($callbacks as $callback) {
$callback();
}
}
5.6

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Argument Unpack (AKA: SPLAT)
5.6

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Splat Syntax
… $variable
5.6

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Splat Syntax
fn(… $variable);
5.6

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• The opposite of variadics, unpack an array (or similar) as arguments
• No more call_user_func_array() (which is “slow”)
• Valid for any argument list (including new foo(… $var))
• Must be at the end of the argument list
• Use it multiple times!
Splat
5.6

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Splat
function test(...$args) { var_dump($args); }
test(1, 2, 3); // [1, 2, 3]
test(...[1, 2, 3]); // [1, 2, 3]
test(...new ArrayIterator([1, 2, 3])); // [1, 2, 3]
5.6

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Splat
$args1 = [1, 2, 3];
$args2 = [4, 5, 6];
test(...$args1, ...$args2); // [1, 2, 3, 4, 5, 6]
test(1, 2, 3, ...$args2); // [1, 2, 3, 4, 5, 6] 
test(...$args1, 4, 5, 6); // [1, 2, 3, 4, 5, 6]
5.6

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Feedback & Questions:  
Feedback: https://joind.in/ 
Twitter: @dshafik
Email: [email protected]
Slides: http://daveyshafik.com/slides
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[php[world] 2014] PHP 5.NEW: The Best Bits

[php[world] 2014] PHP 5.NEW: The Best Bits

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