> -size t
> - = case t of
> - Tip -> 0
> - Bin sz _ _ _ -> sz
> +size = go
> + where
> + go Tip = 0
> + go (Bin sz _ _ _) = sz
> +{-# INLINE size #-}
Perhaps just
size Tip = 0
size (Bin sz _ _ _) = sz
would suffice :-)
Yes, you're right. This function doesn't actually benefit from W/W as it doesn't have any higher-order arguments, dictionaries or polymorphic arguments.
I will take a second pass over all the code after the proposal period is over. With fresh eyes I might be able to spot more things that could be fixed/improved.