Hi! Just a couple of words to introduce myself: I am from Denmark, but currently living in Nicaragua, where my wife is employed at the Danish embassy. I suppose this means that my current job title is "spouse". Before moving, I made a living as a Data Warehouse programmer/analyst. Having more time on my hands, I decided to spend some of it learning C++. In my experience, one of the best ways to learn a programming language is by looking at (and possibly trying to improve) existing code, preferably of good quality. Which is why I am now showing up on the boost mailing list. I have spent some time playing around with the rational.hpp file, and have made some improvements. Most important is probably operator<, where my new version is completely safe from overflow and (I think) considerably faster. Other features are: a member template for converting between different types of rationals, functions inverse() and power(). Should I put my version of rational.hpp on the sandbox CVS, or mail it to somebody - or is it not relevant at this time? Anyway, considering the call for new features: Maybe the class should have a representation of +-infinity and NAN (the latter follows logically from the former, because infinity*0->NAN). There may be quite a lot of cases where it is not the best solution to throw exceptions for divisions by zero, e.g. a spreadsheet or calculator application, where the user may do all kinds of funny things - when a division by zero occurs, we just want to mark the affected variable as infinite, and write "DIV/0" or something similar in the relevant space in the application UI. The easiest way to accomplish this is to implement it as a selectable feature in the rational class, rather than checking for zero before each division, or setting up try...catch blocks around all the division operations. Of course, the introduction of NAN rationals makes the class only partially ordered (if we follow the floating-point standard, where all comparison operations involving NAN types return false). --- Søren P.S. Have I posted this reply to the call for features in the right way? If not, what is the right way, using Opera for newsgroups and mail?