Dear All, The docs for the proposed is_ordered say: The function is_ordered(sequence, predicate) returns the point in the sequence where the predicate does not hold. It does that by comparing adjacent pairs of elements in the sequence to see if the predicate is satisfied. If all adjacent pairs satisfy the predicate, then it will return one past the last element of the sequence. OK. If the sequence has less than two elements, it returns the last element of the sequence. In other words, sequences of length zero and one are considered to be ordered - using any possible criteria. Shouldn't that say "it returns one past the last element"? Also, regarding the name: I would expect any "is_something" function to return a boolean. Since this returns an iterator I would have called it something like find_disorder. (There is a good chance that an iterator is convertible to bool, so one could mistakenly write "if (is_ordered(begin,end)) { ... }".) Regards, Phil.