There were recently many letters on the subject of Enum (a,b). To my mind, this is not so important matter to design the standard enumeration for pairs. For, suppose the programmer needs to enumerate (a,b). There are infinitely many good ways to map, for example, Integer to (Integer,Integer) - even bijectively. The programmer chooses the enumeration that fits one's particular task. Another enumeration is likely to lead to the algorithm much more expensive. How often the standard enumeration will fit? Recall the sorting task. Here we have sortBy, and the user chooses the parameter <comparison> to get the needed sorting. Similarly, one may set the comparison on (a,b) to obtain the enumeration on (a,b) subdued to this comparison and any enumerations on `a', `b'. This may have sense. But it needs thinking and design. ------------------ Sergey Mechveliani [EMAIL PROTECTED]
