Equivalent of python's **kwargs in php [duplicate] - php

Question

In C#, there is a new feature coming with 4.0 called Named Arguments and get along well with Optional Parameters.
private static void writeSomething(int a = 1, int b = 2){
// do something here;
}
static void Main()
{
writeSomething(b:3); // works pretty well
}
I was using this option to get some settings value from users.
In PHP, I cannot find anything similar except for the optional parameters but I am accepting doing $.fn.extend (jQuery) kind of function :
function settings($options)
{
$defaults = array("name"=>"something","lastname"=>"else");
$settings = array_merge($defaults,$options);
}
settigs(array("lastname"=>"John");
I am wondering what kind of solutions you are using or you would use for the same situation.

Answer 1

As you found out, named arguments don't exist in PHP.
But one possible solution would be to use one array as unique parameter -- as array items can be named :
my_function(array(
'my_param' => 10,
'other_param' => 'hello, world!',
));
And, in your function, you'd read data from that unique array parameter :
function my_function(array $params) {
// test if $params['my_param'] is set ; and use it if it is
// test if $params['other_param'] is set ; and use it if it is
// test if $params['yet_another_param'] is set ; and use it if it is
// ...
}
Still, there is one major inconvenient with this idea : looking at your function's definition, people will have no idea what parameters it expects / they can pass.
They will have to go read the documentation each time they want to call your function -- which is not something one loves to do, is it ?
Additionnal note : IDEs won't be able to provide hints either ; and phpdoc will be broken too...

Answer 2

You can get around that by having an array such as $array= array('arg1'=>'value1');
And then let the function accept the array such as function dostuff($stuff);
Then, you can check arguments using if(isset($stuff['arg1')){//do something.} inside the function itself
It's just a work-around but maybe it could help

Answer 3

You can fake C++-style optional arguments (i.e. all optional arguments are at the end) by checking for set variables:
function foo($a, $b)
{
$x = isset($a) ? $a : 3;
$y = isset($b) ? $b : 4;
print("X = $x, Y = $y\n");
}
#foo(8);
#foo();
It'll trigger a warning, which I'm suppressing with #. Not the most elegant solution, but syntactically close to what you wanted.
Edit. That was a silly idea. Use variadic arguments instead:
// faking foo($x = 3, $y = 3)
function foo()
{
$args = func_get_args();
$x = isset($args[0]) ? $args[0] : 3;
$y = isset($args[1]) ? $args[1] : 3;
print("X = $x, Y = $y\n");
}
foo(12,14);
foo(8);
foo();