On Tue, Aug 12, 2014, at 11:11 PM, Dimitri DeFigueiredo wrote: Hi G Akash, Is that the only solution? I thought about that. The problem with it is that it changes the Set type class. I want the Set type class to be able to contain elements of any type, not just members of Ord. I think the type class represents a "Set" interface that is general. It is the implementation using trees that is only available for Ordered types. And there may be other implementations that don't need this constraint. So, if possible, I don't want to change the Set type class. Isn't there another way to fix it? There are a variety of ways to deal with this using language extensions, such as: [1]https://gist.github.com/ktvoelker/af613fe5308b748b4606 -Karl References 1. https://gist.github.com/ktvoelker/af613fe5308b748b4606