Ben Franksen writes:
jerzy.karczmarczuk@info.unicaen.fr wrote: ...
Does *MATH* answer the question what is: (0/0)==(0/0) ? Nope!
Exactly. So why try to give an answer in Haskell? MATH says: the expression 0/0 is undefined, thus comparing (0/0)==(0/0) is undefined, too. I would expect Haskell to say the same.
I don't know whether you are serious, or you are pulling my leg... Let's suppose that it is serious. When math says that something is undefined, in my little brain I understand that there is no answer. NO answer. Is this the "undefined" you want to have? The bottom non-termination? Now, this is obviously the *worst* possible reaction of the system, the IEEE indefinite is much better, at least you know what had happened. Would you propose the non-termination as the issue of all "errors", such as negative argument to the real sqrt, etc? Well, as you wish... But don't write medical software, please... Jerzy Karczmarczuk