subStr (Retrieves part of a string)
info("str subStr(str _text, int _position, int _number)");
info("Retrieves part of a string.");
info("_text - The original string.");
info("_position - The position in _text to begin the new string.");
info("_number - The number of characters to select from _position onwards.");
info("subStr(\"ABCDEFG\",2,4) " + subStr("ABCDEFG",2,4));
info("subStr(\"ABCDEFG\",5,-3) " + subStr("ABCDEFG",5,-3));