Put this in the repo so Arthur and I can discuss it.

src/RangeSet.h

@@ -0,0 +1,67 @@
+#ifndef RANGESET__H
+#define RANGESET__H
+
+#include <list>
+
+#include <boost/foreach.hpp>
+
+class RangeSet
+{
+
+public:
+
+	typedef std::pair<int, int>							Range;
+	typedef std::list<Range>::iterator					iterator;
+	typedef std::list<Range>::const_iterator			const_iterator;
+	typedef std::list<Range>::reverse_iterator			reverse_iterator;
+	typedef std::list<Range>::const_reverse_iterator	const_reverse_iterator;
+	static const int RangeSetAbsent = -1;
+
+protected:
+
+	std::list<Range> mRanges;
+
+public:
+
+	RangeSet()					{ ; }
+
+	bool hasValue(int) const;
+	int getFirst() const;
+	int getNext(int) const;
+	int getLast() const;
+	int getPrev(int) const;
+
+	bool setValue(int);
+	void setRange(int, int);
+	bool clearValue(int);
+	void clearRange(int, int);
+
+	// iterator stuff
+	iterator begin()						{ return mRanges.begin(); }
+	iterator end()							{ return mRanges.end(); }
+	const_iterator begin() const			{ return mRanges.begin(); }
+	const_iterator end() const				{ return mRanges.end(); }
+	reverse_iterator rbegin()				{ return mRanges.rbegin(); }
+	reverse_iterator rend()					{ return mRanges.rend(); }
+	const_reverse_iterator rbegin() const	{ return mRanges.rbegin(); }
+	const_reverse_iterator rend() const		{ return mRanges.rend(); }
+};
+
+inline RangeSet::const_iterator	range_begin(const RangeSet& r)	{ return r.begin(); }
+inline RangeSet::iterator		range_begin(RangeSet& r)		{ return r.begin(); }
+inline RangeSet::const_iterator	range_end(const RangeSet& r)	{ return r.end(); }
+inline RangeSet::iterator		range_end(RangeSet& r)			{ return r.end(); }
+
+namespace boost
+{
+	template<> struct range_mutable_iterator<RangeSet>
+	{
+		typedef RangeSet::iterator type;
+	};
+	template<> struct range_const_iterator<RangeSet>
+	{
+		typedef RangeSet::const_iterator type;
+	};
+}
+
+#endif