Henning Thielemann wrote:

On Sun, 4 Jul 2010, Michael Mossey wrote:

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Henning Thielemann wrote:

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On Sun, 4 Jul 2010, Michael Mossey wrote:

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I can solve a simpler problem which is

computeSoundedEnd :: Item -> [Item] -> Loc computeSoundedEnd firstNote notes = compSndEnd (pitch firstNote) notes

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You will certainly not be able to make use of foldl or foldr, but you may use a manual recursion instead. Just like

computeAllEnds :: [Item] -> [Item]

What makes it harder than this is that the original document is not a single list of Item's--they are broken into measures.

That is, you want a function of type

computeAllEnds :: [Measure] -> [Measure]

?

Right, although it occurs to me that it might be superior to represent the document as [Item] and give Item a measure-number attribute. There are also other measure attributes, so in that case the doc would look like: data Doc = Doc [MeasureInfo] [Item]