Declaring Variable Types in PHP?

Question

I was trying to get my Netbeans to autocomplete with PHP, and I learned that this code is valid in PHP:

function blah(Bur $bur) {}

A couple of

Answer 1

Does this actually impose any limits on what type of variable I can pass to the blah method?

This is called type hinting. According to the PHP documentation that I just linked to, yes, it does impose limits on the argument type: "Failing to satisfy the type hint results in a catchable fatal error."

How can I declare the type of a variable in PHP if I'm not in a function?

Read type juggling. You can't explicitly define a variable's type in PHP, its type is decided by the context it is used in.