PHP 7.1中的隐式void返回？

Question

I found in here the new spec: https://wiki.php.net/rfc/void_return_type

function lacks_return(): void {
    // valid
}
function returns_nothing(): void {
    return; // valid
}
function returns_void(): void {
    return void; // valid
}

Ask: Do you know what happens behind the scene. Will the lacks_return function return actually void?

Answer 1

You could have tested this yourself pretty easily:

function lacks_return(): void {
}

function returns_nothing(): void {
    return;
}

echo gettype(lacks_return()); // NULL
echo gettype(returns_nothing()); // NULL

So the answer is yes - there is an implicit empty (null) return so you could either use an empty return or skip it completely. Which kind of makes sense - returning nothing is the same as not returning anything?