The PHP development team is proud to announce the immediate availability of PHP 5.5.0. This release includes a large number of new features and bug fixes.

The key features of PHP 5.5.0 include:

• Added generators and coroutines.
• Added the finally keyword.
• Added a simplified password hashing API.
• Added support for constant array/string dereferencing.
• Added scalar class name resolution via ::class.
• Added support for using empty() on the result of function calls and other expressions.
• Added support for non-scalar Iterator keys in foreach.
• Added support for list() constructs in foreach statements.
• Added the Zend OPcache extension for opcode caching.
• The GD library has been upgraded to version 2.1 adding new functions and improving existing functionality.
• A lot more improvements and fixes.

Changes that affect compatibility:

• PHP logo GUIDs have been removed.
• Windows XP and 2003 support dropped.
• Case insensitivity is no longer locale specific. All case insensitive matching for function, class and constant names is now performed in a locale independent manner according to ASCII rules.

For users upgrading from PHP 5.4, a migration guide is available detailing the changes between 5.4 and 5.5.0.

For a full list of changes in PHP 5.5.0, see the ChangeLog.