[birkbork]

I stand corrected.

PHP does not have type hint for their internal datatypes (int, float, string). Only array is supported. Type hinting for your custom datatypes is supported, when used as function arguments.

Also hack introduces type hint for function return type.

[TazeTSchnitzel]

Scalar (int, float, string) type hinting may be added in a future PHP version, and there's currently an RFC for return types (I expect it'll pass myself). PHP already let you type hint for classses.

[spaux]

You can also hint on interfaces. If strict typing is important, I use the SPL primitive wrapper classes like SplString or SplInt http://php.net/manual/en/class.spltype.php

[birkbork]

Cool! I wasn't aware of the RFC. Must be this one then? https://wiki.php.net/rfc/returntypehinting

[TazeTSchnitzel]

Yep.