nctive --&gt;keys . A user
may edit the frames (within reason!) and thereby change the internally used
algorithms. For example, a user can implement a different buffering scheme for
input characters. </P>

<H3>Accessing the lookahead token</H3>

<P>The generated parser offers the lookahead token <I>t</I> that can be
used to access the next token in the input stream (i.e. the one that has
already been scanned but not yet parsed). The following example shows one
way of computing the start and the end position