Normally I agree with you, apfelmus, but here at least I have to differ!
On Mon, Oct 13, 2008 at 11:50 AM, apfelmus
*HTML> toString $ tag "b" [] [tag "i" [] [text "<>"], text "test"] "<b><i><></i>test</b>"
I'd say the big problem is that your embedded language for describing HTML is way more complex for a domain expert than doc = renderHTML $(q "<b><i>#{v1}</i>#{v2}</b>") where v1 = "<>" v2 = "test" which, while somewhat error-prone in the HTML string itself, is much more likely to get used than an embedded language. One thing that "ideal in theory" solutions seem to miss out on a lot is usability; SafeString seemed to strike a great balance there, which is why I think it has been brought up as a great example of solving this problem in the real world. There's a reason why Ruby is taking off despite its complete lack of safety; writing code using it is genuinely enjoyable and Rails solves a lot of problems elegantly. I wouldn't want to use it for a big project; I have performance and reliability concerns, but attempts to "ruby-ify" bits of Haskell where safety can be validated via a small amount of inspection are welcome! -- ryan