id	summary	reporter	owner	description	type	status	priority	milestone	component	version	resolution	keywords	cc	os	architecture	failure	difficulty	testcase	blockedby	blocking	related
3870	Avoid Haddock-links to the Prelude	waern		"If you're generating documenatation that links to the base package, you will see that some links to standard types go to the `Prelude` and some to the hierarchical libararies. For example, `Int` goes to `Prelude.Int`, while `Either` goes to `Data.Either.Either`.

This happens because the `Prelude` imports some types from the hierarchical libraries, while some are imported directly from internal GHC modules (e.g. `GHC.Base`). In the first case, the hierarchical module is choosen as the best place to link to since it's closer than the `Prelude` in the topological sort to the original module. In the latter case, the hierarchical module and the `Prelude` are of equal number of imports away from the original module, so none is considered a better place to link to. In this case one of the modules is arbitrarily chosen and it happens to be the `Prelude`. 

I think it would be nice if the links would always go to the hierarchical libraries. Maybe the best way to achieve that would be to add `{-# OPTIONS_HADDOCK NotHome #-}` to the `Prelude`. This flag is not yet documented (I should get around to that). It tells Haddock to prefer linking to another module if one is available."	feature request	new	lowest	7.6.2	Documentation	6.12.1				Unknown/Multiple	Unknown/Multiple	Documentation bug