On Feb 13, 2009, at 2:11 PM, Jonathan Cast wrote:
The compiler should fail when you tell it two mutually contradictory things, and only when you tell it two mutually contradictory things.
By definition, it's not a contradiction when the symbol is unambiguously typeable. Do you think math textbooks are filled with contradictions when they give '+' a different meaning for vectors than matrices or real numbers???
Type is implicitly or explicitly a part of the definition of every function. It's not the name that need be unique, but the name over a given domain. When two functions have different domains, the same name can be unambiguously used to describe both of them.
Adding information cannot remove a contradiction from the information set available to the compiler.
But it can and often does, for example, for [] or 4. What's the type of either expression without more information?
Regards, John A. De Goes N-BRAIN, Inc. The Evolution of Collaboration http://www.n-brain.net | 877-376-2724 x 101 _______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
