[Haskell-cafe] What is the meaning of tilde ("~") symbol

Tony Morris tonymorris at gmail.com
Sun Feb 14 18:12:15 EST 2010

Stephen Tetley wrote:
> Hi Evan
> Singleton (aka wrap) would be nice - isn't it called Pointed in the
> typeclassopedia but not otherwise existent? I suppose its missing by
> historical accident rather than design.
> I frequently use Semigroup (append but no zero) - there is one on
> Hackage without any instances:
> http://hackage.haskell.org/package/algebra
I do too. I also wish there was an associative: class F f where k :: f a
-> f a -> f a without the zero component.

Tony Morris

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