Some PHP people still aren't using namespaces. In this talk I tried to help anyone who hasn't made the move to do so.

1. PHP Namespaces and Autoloading
By Vic Metcalfe
GTA-PHP
Pre-Talk
Slides

2. Autoloading since 5.0
Namespaces since 5.3

3. Global Namespace
<?php
class Grid {
//...
}
<?php
class Grid {
//...
}

4. You organize your files
using folders
Organize your classes
using namespaces

5. With Namespaces
<?php
namespace DataViews;
class Grid {
//...
}
<?php
namespace Charting;
class Grid {
//...
}

6. Sub-Namespaces
<?php
namespace AcmeIncCharting;
class Grid {
//...
}
<?php
namespace AcmeIncDataViews;
class Grid {
//...
}
<?php
$dataView = new AcmeIncDataViewsGrid;
$chart = new AcmeIncChartingGrid;

7. Importing Namespaces
<?php
namespace Lorem;
class Foo
{
function __construct()
{
echo "I'm a Foo.n";
}
}
<?php
namespace Ipsum;
class Bar
{
function __construct()
{
echo "I'm a Bar.n";
}
}
<?php
require_once('foo.php');
require_once('bar.php');
use LoremFoo;
use IpsumBar;
new Foo;
new Bar;

8. Aliasing Namespaces
<?php
namespace Lorem;
class Foo
{
function __construct()
{
echo "Lorem Foo.n";
}
}
<?php
namespace Ipsum;
class Foo
{
function __construct()
{
echo "Ipsum Foo.n";
}
}
<?php
require_once('lorem.php');
require_once('ipsum.php');
use LoremFoo as LorumFoo;
use IpsumFoo as IpsumFoo;
new LorumFoo;
new IpsumFoo;

9. Before
Autoloading:
The Dark AgesDe Molay, last Grand Master of
the Knights-Templars
(Public Domain Image)

10. app.php
The list of requires
could get very long!
foo.php bar.php
<?php
class Foo
{
function __construct()
{
echo "I'm a Foo.n";
}
}
<?php
class Bar
{
function __construct()
{
echo "I'm a Bar.n";
}
}
<?php
require_once('foo.php');
require_once('bar.php');
$foo = new Foo;
$bar = new Bar;

11. Used with permission from http://martybpix.deviantart.com/art/Fluttershy-Yay-Opening-308959593
Hurray for
__autoload!

12. autoloader.php
app.php
<?php
function __autoload($className)
{
$fileName = strtolower($className) . ".php";
require_once($fileName);
}
<?php
require_once('autoloader.php');
$foo = new Foo;
$bar = new Bar;
Remember: The class Foo lives in
foo.php, and Bar lives in bar.php.

13. You can only have one
__autoload() function
Used with permission from http://mcmxvii.deviantart.com/art/lonely-puppy-63391140

14. spl_autoload_register
Used with permission from https://www.flickr.com/photos/ncfc/2096277438

15. Class
Names
File
Names
Enter PSR-0

16. PHP Framework Interop
Group
• Called PHP-FIG
• These are the people responsible for PSR’s (PSR =
“PHP Standards Recommendation”)
Which PSR’s prescribe namespace usage?
ALL OF THEM!
PSR-0
Autoloading
PSR-1
Coding Standard
PSR-2
Style Guide
PSR-3
Logger Interface
PSR-4
Autoloading

17. PSR-0
namespace Vendor(NameSpace)*;

18. PSR-0
namespace Vendor(NameSpace)*;
Namespaces must start
with a vendor name

19. PSR-0
namespace Vendor(NameSpace)*;
After the vendor you can
specify as many sub-
namespaces as you wish,
or none at all

20. PSR-0
Namespaces are converted directly to folder names.
Class names are split by underscores, and then
converted to folders and file names:
class Foo_Bar
FooBar.php
namespace Lorem_Ipsum;
class Foo_Bar
Lorem_IpsumFooBar.php

21. PSR-0
project/
src/
AcmeInc/
FooBarPackage/
Services/
Foo.php
Bar.php
tests/
AcmeInc/
FooBarPackage/
Services/
FooTest.php
BarTest.php
Enter PSR-4

22. PSR-4
Namespace Prefixes
Base Directories
Got rid of the weird _ to folder name thing,
and addressed issues around case sensitivity,
but most importantly…

23. PSR-4
project/
src/
Foo.php
Bar.php
tests/
FooTest.php
BarTest.php
project/
src/
AcmeInc/
FooBarPackage/
Services/
Foo.php
Bar.php
tests/
AcmeInc/
FooBarPackage/
Services/
FooTest.php
BarTest.php

24. PSR-4
Base Directory Namespace Prefix
./project/src/ AcmeIncFooBarPackageServices
./project/tests/ AcmeIncFooBarPackageServices

25. PSR-4 lets you shorten
your paths.
It does not allow you use
_ to build paths.

26. Composer

27. I did a talk on Composer in
October 2013
It was light on slides and heavy on live demo.
Here’s my raw notes:
https://gist.github.com/zymsys/23c0d7824730a2aa2063

28. Other Notable Autoloaders
Symphony
ClassLoader
spl_autoload
Zend
AutoloaderFactory

29. Performance

30. Troubleshooting

31. Questions?

32. Thanks for joining us tonight.
See you Friday at TrueNorthPHP!