[Haskell-cafe] Re: Converting IO [XmlTree] to [XmlTree]

[Martijn van Steenbergen]

Tillmann Rendel wrote:
> Achim Schneider wrote:
>> In other words:
>>
>> 1) Explain Pointed
>> 2) Explain Functor
>> 3) Explain Applicative
>> 4) Explain Monad
> 
> Why Pointed first? Functor seems more useful and more basic.

They are in order of power: every monad is an applicative; every 
applicative is a functor; every functor is pointed.

Though I can't think of any non-functor pointiness at the moment.

Martijn.