Question

I’m sure there’s a very easy explanation for this. What is the difference between this:

function barber($type){
    echo "You wanted a $type haircut, no problem\n";
}
call_user_func('barber', "mushroom");
call_user_func('barber', "shave");

… and this (and what are the benefits?):

function barber($type){
    echo "You wanted a $type haircut, no problem\n";
}
barber('mushroom');
barber('shave');

Answer 1

Always use the actual function name when you know it.

call_user_func is for calling functions whose name you don’t know ahead of time but it is much less efficient since the program has to lookup the function at runtime.