Lookup module and package defining <<x>?

[Marc Weber]

Has somene already implemented something like:

$ghc-pkg --where-from ParseError
package parsec: defining modules: Text.ParserCombinators.Parsec.Error, Text.ParserCombinators.Parsec

?

lambdabot @index does what I want, but not with my libs installed only
locally..

This might be used by any developement system for easily importing
modules..

If not I'll start working on this and I'll post again after
   needing help ;)
or finishing

It can't be that hard because there is already
ghc-pkg list and ghc --show-iface ...

Marc