<?php
class Foo
{
        private $var1;
        private $var2;

        public function Foo($val)
        {
                $this->init($val);
                $this->doSomething();
        }

        private function init($val)
        {
                $this->var1 = $val;
        }
        
        private function doSomething()
        {
                $this->var2 = sqrt($this->var1);
        }

        public function getResult()
        {
                return $this->var2;
        }
}
?>