Separate warnings for unused local and top-level bindings

[magunter]

I'd like separate warnings for local and top-level
unused binds.  I often have "unused" top-level
functions which I use from ghci.  I'd like to avoid
warnings for
these while retaining the warnings for unused local
bindings (which can always be eliminated by prefix the
name with an underscore.)

[simonmar]

Logged In: YES 
user_id=48280

Moved to feature requests

[byorgey]

Would any developers care to guess at the difficulty of this feature? Could this make a good project for someone just starting to get their feet wet hacking on ghc?

[mboes]

I doubt the usefulness of this feature since any top-level function that is mentioned in the export list of the module won't trigger a warning. It is confusing to see dead code in a module and so top-level functions that aren't used should probably just be commented out.

However, this feature does come handy when using records: it often happens that a field name isn't used in a module, hence triggering a warning.

[igloo]

Replying to byorgey:

Would any developers care to guess at the difficulty of this feature? Could this make a good project for someone just starting to get their feet wet hacking on ghc?

I'd say so. It would probably be worth discussing the design on the cvs-ghc list first, though.