Something wrong with disregarding a returned value from a function in PHP

Question

For instance:

// somefile.php
function doSomething() {
    // do lots of code, whatever...
    return $something;
}

// mainfile.php
include "somefile.php"
doSomething(); // ignored the return value, we don't need it here

What happens when a function in PHP returns a value but we don't care about it? Is something wrong with this behavior or should we always get the variable even if we'll never used it outside the function scope? How does PHP manage it's resources by returning a value that won't be used outside of the function scope?

Answer 1

The return value is discarded. There is nothing wrong with doing that. Even functions without an explicit return do return null implicitly:

function foo() {}
var_dump(foo());  // NULL

Answer 2

There is nothing wrong with that, but

// do lots of code, whatever...

should make you somewhat suspicious. If you do not need the return value, chances are the function is doing too much. Check if the effect you actually want to achieve by calling the function can be extracted into a separate function. If so, do so and call this one instead.