title: why swift function with variadic parameters can not receive an array as argument
body: <p>as the title, why swift variadic parameters cannot receive an array as the argument? 
  for instance:</p>
  
  <pre><code>func test(ids : Int...){
      //do something
  }
  //call function test like this failed
  test([1,3])
  //it can only receive argument like this
  test(1,3)
  </code></pre>
  
  <p>Sometimes, I can only get array data, and I also need the function can receive variadic parameters, but not an array parameter. Maybe I shoud define two function, one receive array parameter, and another receive variadic parameter, is there any other solution except this one?</p>