Bruno,
On Thu, Sep 24, 2009 at 1:20 AM, Bruno Oliveira
Hello Brad,
I believe that the problem you encountered is not quite the expression problem (which is about adding new constructors and functions modularly), but rather about refining *existing* constructs with more specific types. One could argue that they are related though but, for your own sake, you may want to use a term that more directly points to the problem in question. [...]
Indeed, for finding existing approaches to this problem, it is prudent to know what others refer to it as. If you squint a little, this looks like an instance of the expression problem: type classes are (families of) constructors, and instances of those type classes (i.e., interpretations) are functions on those constructors. Sincerely, Brad