I was inspecting a class from a phpoffice vendor called phpspreadsheet and found the following function in the Calculation.php module ... not a problem, but I would like to understand the meaning of this function, I have programmed it in php for 10 years and never had seen 3 points within the parameter of a function. I wonder what this means, what causes it or what it is for! Follow the function
private static function mkMatrix(...$args)
{
return $args;
}
Since 5.6 has been implemented in function arguments as ... , known as spread operator . This means that the function / method will receive a variable amount of arguments and treat it as a array .
See:
function sum(...$numbers) {
$acc = 0;
foreach ($numbers as $n) {
$acc += $n;
}
return $acc;
}
echo sum(1, 2, 3, 4);
The return of this function will be
10
You can also use to transform an array / tranversable into a list:
function add($a, $b) {
return $a + $b;
}
echo add(...[1, 2])."\n";
$a = [1, 2];
echo add(...$a);
@edit
In previous versions, up to 5.5 , when passing a variable amount of parameters into a function, they were handled using the functions
func_num_args , func_get_arg , func_get_args
Source: Function Arguments
Since PHP 5.6 you can also use the% with% notation:
varied functions can now be implemented using ...$numbers operator instead of relying on func_get_args ().
function f($req, $opt = null, ...$params) {
// $params is an array containing the remaining arguments.
printf('$req: %d; $opt: %d; number of params: %d'."\n",
$req, $opt, count($params));
}
f(1);
f(1, 2);
f(1, 2, 3);
f(1, 2, 3, 4);
f(1, 2, 3, 4, 5);
The above example will be displayed:
$ req: 1; $ opt: 0; número de params: 0
$ req: 1; $ opt: 2; número de params: 0
$ req: 1; $ opt: 2; número de params: 1
$ req: 1; $ opt: 2; número de params: 2
$ req: 1; $ opt: 2; número de params: 3
source: link