SPAN> InputFilter&gt;
<SPAN CLASS='keyword'>bool</SPAN> test_filter_pair( OutputFilter first, 
                       InputFilter second,
                       <SPAN CLASS='keyword'>const</SPAN> std::string&amp; data );

<SPAN CLASS='keyword'>template</SPAN>&lt;<SPAN CLASS='keyword'>typename</SPAN> OutputFilter, <SPAN CLASS='keyword'>typename</SPAN> InputFilter, <SPAN CLASS='keyword'>typename</SPAN> Source&gt;
<SPAN CLASS='keyword'>bool</SPAN> test_filter_pair( OutputFilter first, 
                       I