On 2007-10-11, Jonathan Cast
Yes. I am very eager to criticize your wording. To wit, I'm still failing to understand what your position is. Is it fair to say that your answer to my question, why pi has no default implementation, is `in fact, pi shouldn't be a method of Floating anyway'?
That was how I was reading him.
Btw: I am arguing that I (still) don't understand why the line
pi = acos (-1)
or something like it doesn't appear at an appropriate point in the Standard Prelude, given that the line
pi :: a
appears nearby said point. I am eager to be enlightened. But I haven't been, yet.
You would have to ask the committee. But I think it's a bad idea to have such a default (or 4 * atan 1, or ...) because of calculational issues. It's not a useful default, except for toy uses. Yeah, it works "fine" for float and double on hardware with FPUs. But I want to be told that I haven't implemented it, rather than it getting a really awful default. Most of the defaulting in other classes are minor wrappers, such as converting between (<=) and compare, not actual algorithmic implementations, which can pull in strongly less efficient implementations. -- Aaron Denney -><-