On Fri, Jul 02, 2010 at 08:48:07PM -0400, Brandon S Allbery KF8NH wrote: > On 7/2/10 17:24 , Gregory Crosswhite wrote: > > The problem with this approach is that the hash context isn't a monoid; you > > can absorb data into the context, but you can't combine two hash contexts to > > form a new one. Thus, the Writer monad won't work for this purpose. > > No? The context is simply a String, which is a monoid, and you can combine > contexts quite meaningfully before you actually compute the final hash (in > fact, that's the whole point!).
The context isn't a string. it is an intermediate state in the algorithm of the hash function. it is usually an opaque binary blob (represented by a ByteString) of a size that is on the order of the final hash (unrelated to the size of the input). John -- John Meacham - ⑆repetae.net⑆john⑈ - http://notanumber.net/ _______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe