Proposed text to specify an interval class in the C++ standard library, with justification and background. Contents I Motivation and Scope 3 II Foundations 3 IIIImpact on the Standard 5 IV Design Decisions 5 IV.1 Design overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 tract model issues . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 IV.3 Data representation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 IV.4 API issues . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 IV.5 Relation to other parts of the standard library . . . . . . . . . . . . . . . . . . . . . 12 IV.6 Other issues . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 V Proposed Text for the Standard 15 26.6 Interval numbers [lib.interval.numbers] 15 26.6.1 Header <interval> synopsis [lib.interval.synopsis] . . . . . . . . . . . . . . . . . . 16 26.6.2 Int...