why does if(function_name()) not work?

Question

Hey guys really quick question, I have a simple test that I was doing to prove a point and it does not work like I expected but I am not sure why it does not work.

function test(){
    echo 'test';
}

if (test()){
    echo 'ok';
}

That was my test. 'ok' is not echoed and I am not sure why. I was testing this because my real code is calling a class method and is also not working.

if($database->addNewUser($user, md5($pass), $userfile, $email, $age)){
    return 0;  //New user added succesfully
}

The method addNewUser executes and does what it should, but the return 0; does not. Anyone have any insight into this?

Answer 1

Your function does not return true. Why would you expect 'ok' to be echoed?

Answer 2

Because your test function is ECHOING not returning..

function test(){
   return true; // what to send back
}

if (test()){ // true was sent back, so.
    echo 'ok';
}

will echo 'ok'.

look at $database->addNewUser() - what's it returning ?

Answer 3

Your function test() doesn't return any value. PHP treats this absence of a value as false, so the body of the if block is never executed.

With your full example, the problem is either than addNewUser doesn't return a value, or it's returning a false value.

Answer 4

You need to return something to indicate success. Either of these would work:

function test(){
    echo 'test';
    return TRUE;
}

or, less desirable, but should still work:

function test(){
    echo 'test';
    return 1;
}

Answer 5

Your test() function does not return a value - I would not expect this to work. Try returning something from it, such as TRUE.