
24 Dec
2008
24 Dec
'08
11:10 p.m.
David Menendez wrote:
This is a great example of why it's a bad idea to introduce new functionality with a Monoid instance. Even if you know the instance exists, mappend is so general that it's difficult or impossible to predict what it will do at a given type.
There should be an explicit function for combining Ordering values lexicographically, with a note in the documentation saying that it's the basis of the Monoid instance.
Agreed. Supposing such an explicit function exists (with proper documentation), would the original example be worth mentioning in or around comparing's documentation? If it saved the next user a couple of minutes of coming up with something similar, I'd be happy. Martijn.