Using namespaces with classes created from a variable

by

Because strings can be passed around from one namespace to another. That makes name resolution ambiguous at best and easily introduces weird problems.

namespace Foo;

$class="Baz";

namespace Bar;

new $class;  // what class will be instantiated?

A literal in a certain namespace does not have this problem:

namespace Foo;

new Baz;     // can't be moved, it's unequivocally \Foo\Baz

Therefore, all “string class names” are always absolute and need to be written as FQN:

$class="Foo\Baz";

(Note: no leading \.)

You can use this as shorthand, sort of equivalent to a self-referential self in classes:

$class = __NAMESPACE__ . '\Baz';

More Related Contents:

  1. What does a \ (backslash) do in PHP (5.3+)?
  2. Parse XML with Namespace using SimpleXML [duplicate]
  3. What are namespaces?
  4. PHP library for parsing XML with a colons in tag names? [duplicate]
  5. parse an XML with SimpleXML which has multiple namespaces [duplicate]
  6. PHP namespace simplexml problems
  7. Can PHP namespaces contain variables?
  8. How to use objects from other namespaces and how to import namespaces in PHP
  9. Unexpected character in input: ‘\’ (ASCII=92) state=1
  10. Autoloading classes in PHPUnit using Composer and autoload.php
  11. PHP how to import all classes from another namespace
  12. Namespace in PHP CodeIgniter Framework
  13. How to get all class names inside a particular namespace?
  14. PHP namespace with Dynamic class name
  15. How to use “root” namespace of php?
  16. SimpleXML: Working with XML containing namespaces
  17. How to use composer packages in codeigniter?
  18. PHP namespaces and “use”
  19. Use php namespace inside function
  20. PHP adding custom namespace using autoloader from composer
  21. SimpleXML SOAP response Namespace issues
  22. How to get attribute of node with namespace using SimpleXML? [closed]
  23. Troubleshooting “The use statement with non-compound name … has no effect”
  24. Class ‘App\Http\Controllers\DB’ not found and I also cannot use a new Model
  25. Using namespaces in Laravel 4
  26. PHP namespace PDO not found
  27. Facebook SDK v4 for PHP Minimal Example
  28. unexpected ‘use’ (T_USE) when trying to use composer
  29. How to generate an Excel document with multiple worksheets from PHP?
  30. Find JSON strings in a string

Leave a Comment