3 May
2011
3 May
'11
8:03 a.m.
There is that formulation, though usually I find I need to do it with
an alternative instead:
altconcat alt [] = alt
altconcat _ (a:as) = go a as
where
go acc [] = acc
go acc (b:bs) = go (acc <> b) bs
Both are "kind of, sort of" bringing you up to a Monoid though...
On 3 May 2011 12:56, Holger Siegel
You have to provide the "neutral" element by yourself: