PHP 5.4 Emerges From the Collapse of PHP 6.0
While the PHP 6.0 project has been abandoned, the upcoming release of PHP version 5.4 early next year will include the best parts of the PHP 6.0 project, including "inline support" for some new languages, such as Japanese and some Chinese dialects.
Another feature of PHP 6.0 called Traits will enable developers to use specific bits of functionality in multiple places within an application. The PHP 6.0 project's goal was to rewrite the PHP language using Unicode instead of ASCII. The problem was that implementation using Unicode took twice the run-time memory, making applications run significantly slower.
Other changes that came from the PHP 6.0 project include the deprecation of features that were going to be removed in version 6.0, but are now being removed in 5.4, such has PHP's Safe Mode, which was created to allow PHP to be run in multisite implementations, but was buggy in practice.
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