[Haskell-cafe] arrow notation

[Ertugrul Söylemez]

Petr Pudlák <petr.mvd at gmail.com> wrote:

>     class Arrow a => ArrowDelay a where
>         delay :: a b c -> a () (b -> c)
>
>     force :: Arrow a => a () (b -> c) -> a b c
>
> Perhaps it would be convenient to have ArrowDelay and the
> corresponding conversions included in the library so that defining and
> using Applicative instances for arrows would become more
> straightforward.

I appreciate the idea from a theoretical standpoint, but you don't
actually have to define an ArrowDelay instance for the notation to work.
The compiler can't check the laws anyway.


Greets,
Ertugrul

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