On 12/3/07, Yitzchak Gale
David Benbennick wrote:
Note that in one sense, people are already prevented from defining a different Bounded instance. Any Bounded instance other than the one suggested in this proposal would fail to obey the axioms of the Bounded class. In other words, there is a unique largest element, and a unique smallest element, an no one can legitimately define a different Bounded instance.
Where are these axioms? I only see the Haddocks in the Prelude:
"Ord is not a superclass of Bounded since types that are not totally ordered may also have upper and lower bounds."
See http://haskell.org/ghc/docs/latest/html/libraries/base-3.0.0.0/Prelude.html#... The first sentence there says "The Bounded class is used to name the upper and lower limits of a type". In other words, you can't just pick any old values for minValue and maxValue.