View source for Haddock/Development ideas

There would be a number of benefits if [[GHC]]'s parser were extended to understand the [[Haddock]] documentation markup and then Haddock changed to use the [[GHC/As a library|GHC API]]:

* Haddock would get full support for GHC's various syntactic extensions.
* Haddock would understand <code>{#- LINE -#}</code> pragmas which would allow it to generate links to the original source code.
* Haddock would get much better error messages.
* Haddock could infer types for functions with no explicit type signature.
* GHCi and IDEs like [[hIDE]] and [[Visual Haskell]] would be able to display API documentation in more convenient ways like in this [http://haste.dyndns.org:8080/ Haste] screenshot:
[[Image:Haste_screenshot_hovering.png]]

* Haddock could accept module parameters with space after "-- #" ("-- #hide" is accepted nowadays, but "-- # hide" not)
* It would be good to have a recursive flag that would operate on all the .hs and .lhs files under a single directory.

* It would be nice if haddock is able to parse more user defined operators like (#).

* Haddock should emit the documentation about instances. For example, it's important to document that the Data.Map instance of Foldable only folds over the values and not the keys.