On Tue, Jan 30, 2007 at 09:38:26AM +0000, Ross Paterson wrote:
On Tue, Jan 30, 2007 at 09:52:01AM +1100, Donald Bruce Stewart wrote:
ross:
why do you need a Put monad, which always seems to have the argument type ()? Monoids really are underappreciated.
For the syntax, and So that people can directly port their code from NewBinary. (The instances are basically unchanged).
And so the successor to binary must have the same interface, and so on forever. The backward compatibility argument seems weak to me, leaving only the advantage of do-notation.
How about having both interfaces, so you can use the one you like better? class Binary t where -- | Encode a value in the Put monad. put :: t -> Put put x = Put ((), build x) -- | Encode a value using the Builder monoid build :: t -> Builder build x = snd (unPut (put x)) -- | Decode a value in the Get monad get :: Get t The downside is that GHC probably wouldn't warn about undefined methods, or would it? Best regards Tomasz