add convenience class for integer range

DataStructures/Range.hpp

@@ -0,0 +1,64 @@
+/*
+
+Copyright (c) 2013, Project OSRM, Dennis Luxen, others
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without modification,
+are permitted provided that the following conditions are met:
+
+Redistributions of source code must retain the above copyright notice, this list
+of conditions and the following disclaimer.
+Redistributions in binary form must reproduce the above copyright notice, this
+list of conditions and the following disclaimer in the documentation and/or
+other materials provided with the distribution.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR
+ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
+ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+*/
+
+#ifndef RANGE_H
+#define RANGE_H
+
+#include <type_traits>
+
+namespace osrm
+{
+
+template <typename Integer> class range
+{
+  private:
+    Integer last;
+    Integer iter;
+
+  public:
+    range(Integer start, Integer end) : last(end), iter(start)
+    {
+        static_assert(std::is_integral<Integer>::value, "range type must be integral");
+    }
+
+    // Iterable functions
+    const range &begin() const { return *this; }
+    const range &end() const { return *this; }
+
+    // Iterator functions
+    bool operator!=(const range &) const { return iter < last; }
+    void operator++() { ++iter; }
+    Integer operator*() const { return iter; }
+};
+
+template <typename Integer> range<Integer> irange(Integer first, Integer last)
+{
+    return range<Integer>(first, last);
+}
+}
+
+#endif // RANGE_H