On Apr 3, 2006, at 1:31 PM, Benjamin Franksen wrote:
wondered about the Ord instance. Wouldn't it be faster to compare
(word-) representations?
I thought about that some. Since the set representation is based
completely on the enumeration, it would be possible for the type
being collected to have a different implementation of Ord. For
instance:
newtype LowerCaseAlpha = LCA Char deriving (Eq, Show)
instance Enum LowerCaseAlpha where
fromEnum (LCA x) = (fromEnum x) - (fromEnum 'a')
toEnum x = LCA $ toEnum $ x + (fromEnum 'a')
instance Ord LowerCaseAlpha where
compare (LCA a) (LCA b)
| a == b = EQ
| a > b = LT
| a < b = GT
Perverted, but possible.
--------------------------------
David F. Place
mailto:[EMAIL PROTECTED]
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