The BOOST_PP_SEQ_FILTER_S macro filters a seq according to a 
			supplied criterion.  It reenters BOOST_PP_SEQ_FOLD_LEFT with 
			maximum efficiency.
		
		
			Usage
		
		
			BOOST_PP_SEQ_FILTER_S(s, pred, data, seq)
		
		
			Arguments
		
		
			- s
- 
				The next available BOOST_PP_SEQ_FOLD_LEFT fold step.
			
- pred
- 
				A ternary predicate of the form pred(s, data, elem).  
				This predicate is expanded by BOOST_PP_SEQ_FILTER for each element in seq
				with the next available BOOST_PP_SEQ_FOLD_LEFT fold step, the auxiliary data, 
				and the current element in seq.  This macro must return a integral 
				value in the range of 0 to BOOST_PP_LIMIT_MAG.  If this 
				predicate expands to non-zero for a certain element, that element is included 
				in the resulting seq.
			
- data
- 
				Auxiliary data passed to pred.
			
- seq
- 
				The seq to be filtered.
			
			Remarks
		
		
			This macro expands pred for each element in seq.  It builds 
			a new seq out of each element for which pred returns non-zero.
		
		
			See Also
		
		
		
			Requirements