Implemented _concat

test/scripts/lib/compound.toy

@@ -1,5 +1,39 @@
 import compound;
 
+{
+	//test array concat
+	{
+		var a = [1, 2, 3];
+		var b = [4, 5, 6];
+
+		var c = a.concat(b).concat(b);
+
+		assert c == [1, 2, 3, 4, 5, 6, 4, 5, 6], "array.concat() failed";
+	}
+
+	//test dictionary concat
+	{
+		var a = ["one" : 1, "two": 2, "three": 3];
+		var b = ["four" : 4, "five": 5, "six": 6];
+
+		var c = a.concat(b);
+
+		assert c.length() == 6, "dictionary.concat().length() failed";
+
+		assert c == ["one" : 1, "two": 2, "three": 3, "four" : 4, "five": 5, "six": 6], "dictionary.concat() comparison failed";
+	}
+
+	//test string concat
+	{
+		var a = "foo";
+		var b = "bar";
+
+		var c = a.concat(b);
+
+		assert c == "foobar", "string.concat() failed";
+	}
+}
+
 //test getKeys
 {
 	var d = ["foo": 1, "bar": 2];