Is it possible to define a function argument as multiple possible types? For example, a function may take a string or an integer to accomplish something. Is it possible to somehow define it like this?
function something(int|string $token) {}
Or is only one type per argument supported?
(mind you, I know I can filter input later on, I just like to have my arguments typed)
Union types have finally been implemented in PHP 8.0, which is due for release near the end of 2020.
They can be used like this:
class Number {
private int|float $number;
public function setNumber(int|float $number): void {
$this->number = $number;
}
public function getNumber(): int|float {
return $this->number;
}
}
No, it is not possible.
Also, type hinting in PHP 5 is now only for classes and arrays. http://php.net/manual/en/language.oop5.typehinting.php
class Foo
{
}
function something(Foo $Object){}
The best you can do is called Type Hinting and is explained here:
http://php.net/manual/en/language.oop5.typehinting.php
In particular, you can hint a class type or an array type, but (as the manual says) "Traditional type hinting with int and string isn't supported." So I guess that what you are trying to accomplish is not possible at this level.
However, you can create your own wrappers, etc. There are probably a thousand ways to handle this.
PHP is dynamically typed - but type hinting has been added to the language - so if you've not hinted the parameter you can pass any type you like:
function something($token)
{
if (is_numeric($token)) {
// its a float, double, integer
} else {
// its a string, array, object
}
}
(off the top of my head I'm not sure how resources are handled).
However if you want to program in a strongly typed language, then (IMHO) you should be using something other than PHP
is_numeric also includes numeric strings, but not resources.