bu yüzden bu 2 gibi işlevlere sahiptir:

function boo(){
  return "boo";
}

ve

function foo(){
  echo "foo";
}

the fist one will return a value, ve the 2nd one will output something to the screen directly.

$var = boo();
foo();

How can I merge these 2 functions into one, ve somehow detect if it's being called to output the result to the screen, or if it's called for getting the return value? Then choose to use return or echo...