Question

I want to write a condition where I want to know if my function needs a return value or it can be executed as a procedure. Basically it should look like:

foo($x) {
    $x++;
    echo $x;
    if(is_return_needed()) {
        return $x;
    }
}

where is_return_needed() is the condition if a return value is needed.

And how it should work:

echo foo(50); // should print AND return 51
bar(foo(50)); // should print AND return 51 to bar() function
foo(50); // should only print the value, because the returned value will not be used

And please don’t tell me there’s no reason to do this. I know I can send an additional boolean argument to the function which will be the condition, but is there a better way to achieve this?

Answer 1

Returning an object (or a large string), PHP will not make a copy of that object/string. That means returning alone, will not slow down your application. I found an article that explains it pretty well.

If the function can avoid building this large object at all, it will become faster. If you change the result of the function outside, or change it just before returning, it will become slower (is has to do the copy then). Building a long string with always adding a small part is very expensive, because every time it has to allocate a new big block of memory.

That said, we would have to see your code, to understand the slowdown you described. Returning a result only sometimes, is a very bad advice, every developer using your code will have a hard time to understand this behaviour. Sooner or later your application will become unstable if you use this often. Actually i find it even dangerous to return mixed typed values, as PHP often does itself.