Robert, On Oct 27, 2005, at 4:59 PM, Robert Dockins wrote:
You could consider creating a monad for the "unstuff" part of the operation that would hide dealing with the FastString, the tupling and the case analysis on Maybe.
Could you elaborate on this a bit please? How would I write and use such a monad?
If you end up doing a lot of instances like this, the monad could well be a win; it also gives you the opportunity to add error reporting during the parse if you want.
This is exactly the problem I'm facing now. Parsing is failing and I need to take apart my pure code just for testing. How would you code this monad?
As a side note, I see you are doing a bunch of operations on lists of properties. If performance is an issue, you might want to consider using Data.Map or similar. If your properties lists can get big, mergeprops looks like a potential problem ( O( n*(n+m) ) each time it's called ).
What would I use as the key for each map entry? If I knew this then I could use a map :-). As it stands, each property is a solid chunk and I can't even extract the name of the attribute it was created with. I don't think Map lets me index on Strings, does it? Since I end up modifying properties a lot I think I sould use monads but I need to read up to get a clear picture. Joel -- http://wagerlabs.com/