Incoherence

Koen Claessen [email protected]
Tue, 23 Oct 2001 12:04:24 +0200 (MET DST)


John Hughes wrote:

 | I noticed today that the presence or absence of a type
 | signature can change the RESULT of an expression in
 | Hugs and GHC nowadays.

This has been a property of the Haskell language since the
defaulting mechanism already!

Here is an example:

  a = let x = 1 in show x               -- == "1"

  b = let x :: Float ; x = 1 in show x  -- == "1.0"


 | Now, what are the proof rules for reasoning about
 | implicit parameters again (:-)?

Now, what are the proof rules about Haskell again :-(?

/Koen.