[Haskell-cafe] Very silly

Andrew Coppin andrewcoppin at btinternet.com
Mon Oct 13 16:17:56 EDT 2008

Jonathan Cast wrote:
> Flexible instances are extroardinarily useful:

I'm sure the GHC team wouldn't have bothered otherwise. ;-)

AFAIK, "flexible instances" just means that absolutely anything can be a 
class instance, right?

> instance Monad m => MonadState s (StateT s m)
> instance MonadState t m => MonadState (s, t) (StateT s m)
> is a useful and not entirely insane instance scheme.

I hadn't realised this required FIs. (Although clearly it demands 
MPTCs.) Man, so many TLAs...

> But yeah, anyone who uses class Silly in real life should be banned from
> coming within a 100 feet of any place where math, science, engineering,
> or software development is carried out or taught.
> I don't know if it's necessary for the good of the Children, but we need
> to start thinking of the poor, defenseless computers as well...

Heh. And I thought *I* was crewl for making my poor PC use Peano 
integers rather than the [vastly more efficient] binary numbers...

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