[Haskell-cafe] What do _you_ want to see in FGL?

Ivan Miljenovic ivan.miljenovic at gmail.com
Tue Apr 27 20:00:33 EDT 2010


On 28 April 2010 08:48, Henning Thielemann
<schlepptop at henning-thielemann.de> wrote:
> Ivan Lazar Miljenovic schrieb:
>> Henning Thielemann <schlepptop at henning-thielemann.de> writes:
>>> I was not happy with the way FGL handles lables so far:
>>>   http://www.haskell.org/pipermail/libraries/2008-February/009241.html
>>
>> Not sure I follow what you want there: you want to remove the whole
>> concept of labels and replace it with the node type?  What about edge
>> labels then?
>
> You can label edges using a Map (i,i) label.

So you don't want the labels to be part of the actual datatype?  And
for users to then have to deal with any labels they want themselves?

If so, I don't think this is feasible; some of the nice parts of FGL
IMHO are how it deals with labels (admittedly, I've had to write and
use my own "((Int,a) -> a') -> g a b -> g a' b" function because it
doesn't have one...).  Removing this would be a step backwards.

How exactly is it bad/a pain to have to deal with specifying "g ()
()", especially since there are some pre-defined "unlabelled" graph
type and function aliases?

-- 
Ivan Lazar Miljenovic
Ivan.Miljenovic at gmail.com
IvanMiljenovic.wordpress.com


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