Paste values from array into string

Question

If have this array:

$a = array("one", "two", "three");

I want to transform this into this string:

$s = "one, two, three";

Is there a paste function in PHP?

Eg:

$s = paste($a, sep=", ");

Answer 1

使用爆破 ：

$s = implode(', ',$a);

Answer 2

$a = array("one", "two", "three");

foreach($a as $value) {
   $string = $string . ($value != '' ? '' : ', ') . $value;
}