What does PHP keyword 'var' do?

This is probably a very trivial question, but I haven't been able to find the answer neither through web search engines, nor on php.net. Please just direct me to where I can read about this, if you haven't got time to explain.

  • What does the 'var' keyword mean in PHP?
  • Are there any differences between PHP4 and PHP5?

  • It's for declaring class member variables in PHP4, and is no longer needed. It will work in PHP5, but will raise an E_STRICT warning in PHP from version 5.0.0 up to version 5.1.2, as of when it was deprecated. Since PHP 5.3, var has been un-deprecated and is a synonym for 'public'.

    Example usage:

    class foo {
        var $x = 'y'; // or you can use public like...
        public $x = 'y'; //this is also a class member variables.
        function bar() {
        }
    }
    

    The var keyword is used to declare variables in a class in PHP 4:

    class Foo {
        var $bar;
    }
    

    With PHP 5 property and method visibility ( public , protected and private ) was introduced and thus var is deprecated.


    I quote from http://www.php.net/manual/en/language.oop5.visibility.php

    Note: The PHP 4 method of declaring a variable with the var keyword is still supported for compatibility reasons (as a synonym for the public keyword). In PHP 5 before 5.1.3, its usage would generate an E_STRICT warning.

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