<?php
$string = 'cup';
$name = 'coffee';
$str = 'This is a $string with my $name in it.';
echo $str. "\n";
eval("\$str = \"$str\";");
echo $str. "\n";
?>

<?php
class myclass {
   function say_hello()
   {
       echo "Hello!\n";
   }
}

$classname = "myclass";

call_user_func(array($classname, 'say_hello'));
?>