On 30/03/07, Chris Eidhof
I'm interested in seeing something like this too. However, I am a big fan of DSL, especially if they're designed correctly. The crux to having a good DSL is thinking: "How do I *really* want to write this?", and starting from there on. I haven't really thought about those things for a web-framework yet.
I'd agree with this. Haskell is astonishingly expressive and can support all kinds of levels of EDSLs. I've been writing forum software in Haskell and came across this decision: do I write my templates in HTML + some code or in Haskell? I couldn't really see any disadvantages to the latter, and the advantages were obviously that I got all the traditional Haskell functions and features, and so on. I still maintain a fairly strict MVC structure within the application; the controllers compute the necessary parameters for the templates and pass them in. For reference, here's one of my templates: -- | The 'V' monad, in which our viewers execute. type V a = WriterT ViewOut (Reader ViewEnv) a type Viewer = V Html -- | View the public profile of a user. vUser :: User -> Viewer vUser u = do tell $ VO { voTitle = usrDisplay u, voBreadcrumbs = singleton indexLink } usr <- asks veUser let hdr = h2 << usrDisplay u dfns = [("Name: ", primHtml $ usrDisplay u), ("Registered at: ", primHtml $ renderCalTime (usrRegistered u)), ("Url: ", toHtml $ hotlink (usrUrl u) << usrUrl u), ("Blurb: ", primHtml $ usrBlurb u)] del = whenPermitted usr RmUser $ hotlink (userUrl u ++ "/delete") << "Delete user" return $ hdr +++ defList dfns +++ cappedOps [del] -- -David House, dmhouse@gmail.com