L'opérateur ...

Permet de gérer un nombre inconnu de paramètres.

//args variable is an array holding the passed function arguments
function function_one(...args)
{
    console.log(args);
    console.log(args.length);
}

function_one(1, 4);
function_one(1, 4, 7);
function_one(1, 4, 7, 0);

function function_two(a, b, ...args)
{
    console.log(args);
    console.log(args.length);
}

//"args" holds only 7 and 9
function_two(1, 5, 7, 9);