This class can be used to iteration over a text string for external arbitraty processing. It traverses a given text string and find all characters that match a given pattern of characters. The strings of consecutive characters that match the pattern are passed to a given callback function for arbitrary processing. The patterns of characters to match can be given as an array of characters strings, or a string that specifies that the match of characters in lower case, upper case, numeric, alphanumeric with lower or upper case, or all characters.