Proposal: Applicative => Monad: Call for consensus

Johan Tibell johan.tibell at
Tue Jan 4 14:11:32 CET 2011

On Tue, Jan 4, 2011 at 1:22 AM, Isaac Dupree
<ml at> wrote:
> You also added defaults for most of the Monad methods, though they're
> obvious and I approve.  The (>>) default might have worse performance than
> the previous default though?  (>>) is used in do-notation desugaring, and
> yet many (most?) Monad instance writers do not explicitly define it, so its
> default makes some difference.  Does anyone know how to test?

Has there been any performance testing of this change? One way to test
it would be test the change on some performance sensitive code that
uses monads. vector-algorithms [1] (which uses the PrimMonad) comes to
mind as a good candidate. Some monadic parser packages, like binary
[2] or attoparsec [3], would be interesting to include in the
performance test too.



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