Although PHP is not a strong-typed language, PHP 5 does support type
hinting for complex data types (objects)
<?php
interface pump {
function get_gas();
}
class premium implements pump {
function get_gas() {
echo "chug!";
}
}
class regular implements pump {
function get_gas() {
echo "chug!";
}
}
class mercedes {
function fill(premium $pump) {
echo $pump->get_gas();
}
}
class pinto {
function fill(pump $pump) {
echo $pump->get_gas();
}
}
$pinto = new pinto;
$pinto->fill(new premium);
$pinto->fill(new regular);
$mercedes = new mercedes;
$mercedes->fill(new premium);
$mercedes->fill(new regular);
?>
