Q:

default param php function

I'd like to just modify the second default param in a function but I don't know how to 
function test($a, $b = "b", $c = "c"){
    echo $a." ".$b." ".$c;
}

test("a");
test("a","z","e");
test("a","z");

I'd like for exemple to use this function keeping $b as default and changing $c.
I try 
test("a",,"f");

But it doesn't work.

A:

This is not possible in PHP nowadays. You have to pass the default value manually like:
test("a", "b", "f"):

There exists a RFC about this: https://wiki.php.net/rfc/skipparams But it hasn't had any success yet.

