[MLton] ML/Lisp/Scheme, =, eq?, eqv?, equal?
Mon, 23 Feb 2004 15:41:09 -0600
The problem with making ML reals an equality type is that floating point
equality doesn't quite work as one would expect of an equality relation.
Note, for example, that it is not reflexive (Nan is not `equal' to Nan).
Also a simple test for equality is almost certainly wrong (because of the
nature of floating point operations).
I remember Richard Kelsey and I talking a lot about many problems with
Scheme's inexact numbers when he was editing R5RS and I was proof reading it.