Find generic versions of the same function

I tried searching for this in Hoogle and found no matches:

Monad m => (e -> ExceptT x m a) -> ExceptT x m (Either e a) -> ExceptT x m a

I then implemented it like this:

onLeft :: Monad m => (e -> ExceptT x m a) -> ExceptT x m (Either e a) -> ExceptT x m a
onLeft h f = f >>= either h pure

Inferring the type signature I get this:

onLeft :: Monad m => (a -> m b) -> m (Either a b) -> m b
onLeft h f = f >>= either h pure

The inferred type signature is one that actually yields results:

Monad m => (a -> m b) -> m (Either a b) -> m b

fromRightM :: Monad m => (a -> m b) -> m (Either a b) -> m b
fromEitherMM :: Monad m => (e -> m a) -> m (Either e a) -> m a
fromEitherOrMM :: Monad m => m (Either e a) -> (e -> m a) -> m a

If Hoogle can somehow infer the generic type signature from the specialised one and put that in the search results, that would help a lot.

No file or test entry point is identified. Start by reproducing the Hoogle search for the specialised ExceptT signature and compare it with the inferred generic signature and related variants shown in the issue; done means generic matches can appear in search results without losing useful specialised matches.