I use __get (and public properties) as much as possible, because they make code much more readable. Compare:
this code unequivocally says what i'm doing:
echo $user->name;
this code makes me feel stupid, which i don't enjoy:
function getName() { return $this->_name; }
....
echo $user->getName();
The difference between the two is particularly obvious when you access multiple properties at once.
echo "
Dear $user->firstName $user->lastName!
Your purchase:
$product->name $product->count x $product->price
"
and
echo "
Dear " . $user->getFirstName() . " " . $user->getLastName() . "
Your purchase:
" . $product->getName() . " " . $product->getCount() . " x " . $product->getPrice() . " ";
Whether $a->b should really do something or just return a value is the responsibility of the callee. For the caller, $user->name and $user->accountBalance should look the same, although the latter may involve complicated calculations. In my data classes i use the following small method:
function __get($p) {
$m = "get_$p";
if(method_exists($this, $m)) return $this->$m();
user_error("undefined property $p");
}
when someone calls $obj->xxx and the class has get_xxx defined, this method will be implicitly called. So you can define a getter if you need it, while keeping your interface uniform and transparent. As an additional bonus this provides an elegant way to memorize calculations:
function get_accountBalance() {
$result = <...complex stuff...>
// since we cache the result in a public property, the getter will be called only once
$this->accountBalance = $result;
}
....
echo $user->accountBalance; // calculate the value
....
echo $user->accountBalance; // use the cached value
Bottom line: php is a dynamic scripting language, use it that way, don't pretend you're doing Java or C#.