Scala's mkString on Groovy.

mkstring.groovy

class WieMkString {
	static String mkString(List self){
		mkString(self, "", "", "")
	}
	
	static String mkString(List self, String sep) {
		mkString(self, "", sep, "")
	}
	
	static String mkString(List self, String start, String sep, String end) {
		def str = start
		if (self.size() > 0){ str += self.head().toString() }
		self.tail().each{
			str += "${sep}${it.toString()}"
		}
		str + end
	}
}

def list = [*1..10]

use(WieMkString){
	assert list.mkString() == "12345678910"
	assert list.mkString("&") == "1&2&3&4&5&6&7&8&9&10"
	assert list.mkString("<td>", ", ", "</td>") == "<td>1, 2, 3, 4, 5, 6, 7, 8, 9, 10</td>"
}