Collecting values from Functors?

[Hal Daume III]

No, you need a fold to do that.

--
 Hal Daume III                                   | hdaume@isi.edu
 "Arrest this man, he talks in maths."           | www.isi.edu/~hdaume

On Wed, 4 Jun 2003, Graham Klyne wrote:

> I'm trying to figure if there's any way I can use (say) monads to collect 
> values from a Functor.
> 
> For example, suppose I have a tree of some values that supports fmap, is 
> there any way I can use the fmap function to collect a list of all the node 
> values?
> 
> #g
> 
> 
> -------------------
> Graham Klyne
> <GK@NineByNine.org>
> PGP: 0FAA 69FF C083 000B A2E9  A131 01B9 1C7A DBCA CB5E
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