[Haskell-cafe] Re: Seeking advice about monadic traversal functions

Martijn van Steenbergen martijn at van.steenbergen.nl
Thu Apr 8 11:02:29 EDT 2010

On 4/6/10 15:31, Heinrich Apfelmus wrote:
> In fact, it doesn't actually work for monads, I think you have to wrap
> it in a newtype. :D The same effect can be achieved with `ap` , though:

Fortunately, by now most (standard) monads are also applicatives. :-)

Besides generalizing to an arbitrary number of arguments, it uses infix 
operators which saves you some parentheses.



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