F='tutorial.html'><IMG BORDER=0 WIDTH=19 HEIGHT=19 SRC='../../../../doc/src/images/up.png'></A>
    <A HREF='tab_expanding_filters.html'><IMG BORDER=0 WIDTH=19 HEIGHT=19 SRC='../../../../doc/src/images/next.png'></A>
</DIV>

<!-- End Nav -->


<A NAME="line_wrapping"></A>
<H2>2.2.4. Line-Wrapping Filters</H2>

<P>
    Suppose you want to write a filter which wraps lines of text to ensure that no line exceeds a certain maximum length. For simplicity, let's not bother to wrap lines at word boundaries or to in