e>
  <p>The second constructor should construct a lexer iterator, which may be used as a iterator traversing over the token sequence, generated by the lexer class.</p>
  <p>The pair of iterators <tt>first</tt> and <tt>last</tt> should represent the input stream to be tokenized by the given lexer class. </p>
  <p>The parameter <tt>pos</tt> contains the initial position information to be used for token generation.</p>
  <p>The parameter <tt>language</tt> controls the required mode  with which the lexer should