Re: [Haskell-beginners] Would you shed light on "undefined values" please?

On Fri, Jun 24, 2011 at 08:13:26AM +0200, Ertugrul Soeylemez wrote:

Bottom arises, as soon as a language is total. This is related to the halting problem. Bottom is the value, which is never computed in the sense that it never results. Only nontotal languages (like Agda) can prevent bottom values from appearing.

That is a funny use of the word "total"; I think you mean "Turing-complete". "Total" is usually used of languages in which it is only possible to define total functions -- such as Agda. Haskell is non-total since it is possible to define non-total, i.e. partial, functions, which are undefined for some inputs. -Brent