ho-interval

This library provides an simple representation of a half-open [x,y) interval defined on set of numbers. That is if you have a set of something that may be compared (operations == and < are defined) than you may group them into intervals.

..,-20,-19.....a...........,0,..........b........ . . .  .  . . . ...........,1000,...

               ^                        ^
               |                        |
               +------------------------+
                     [a, b) interval   

Note: The a-b interval and all other intervals represented by library a left-closed class of a half-open intervals (see here for details).