[Haskell-cafe] Arrows: definition of pure & arr

Ross Paterson ross at soi.city.ac.uk
Sun Feb 17 06:33:18 EST 2008

On Sun, Feb 17, 2008 at 12:00:43AM -0800, Jonathan Cast wrote:
>             arr = pure
>             pure = arr
> [...]
> This example is admittedly kind of silly, but I'm sure someone has a
> passionate attachment to one or both names, so requiring definitions
> to use one or the other would be controversial.

Perhaps not.  I used the name pure for arr in the Fun of Programming
paper, because Richard Bird preferred that name, but it hasn't caught on,
and now the same name is used in the Applicative class.  So perhaps it
should be removed from Arrow.

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