Why does PHP not allow concatenation in static variables?

PHP does not allow concatenation in static variables because static variables must be initialized with constant values at compile time. To work around this limitation, you can use a static constructor method to initialize the static variable with concatenated values at runtime. 

class MyClass {
    public static $staticVar;

    public static function initStaticVar() {
        self::$staticVar = 'Hello' . ' World';
    }
}

MyClass::initStaticVar();
echo MyClass::$staticVar; // Output: Hello World

Keywords

PHP concatenation static variables limitations syntax

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