http://www.upubuntu.com/2012/03/how-to- ... under.html
PHP 5.4.0 is released recently by the PHP development team. This new release encompasses many new features and bug fixes (more than 100 bug fixes) with improvements in terms of performance and memory footprint. Here are the main features in PHP 5.4.0:
Traits (a method of code reuse)
Shortened Array Syntax
A Built-in web server for testing purposes, etc.
For more information about PHP 5.4.0, check this page. In this tutorial we will see how to install / upgrade to PHP 5.4.0 under a system running Ubuntu 11.10 (Oneiric Ocelot) and Ubuntu 12.04 (Precise Pangolin) via PPA.
PHP 5.4.0 Installation
Open the terminal and run this sequence of commands for Ubuntu 11.10/12.04:
sudo add-apt-repository ppa:ondrej/php5
sudo apt-get update
sudo apt-get install php5
For Ubuntu 10.04 LTS, run the following commands (Thanks to Ivan Castellanos for the extra tip):
sudo echo "deb http://ppa.launchpad.net/ondrej/php5/ubuntu lucid main" >> /etc/apt/sources.list
sudo echo "deb-src http://ppa.launchpad.net/ondrej/php5/ubuntu lucid main" >> /etc/apt/sources.list
sudo apt-key adv --keyserver keyserver.ubuntu.com --recv-keys E5267A6C
sudo apt-get update
sudo apt-get install php5
You can check if PHP 5.4.0 is successfully installed with this command:
php5 -v
That's it!