Hoogle 4.0 release (beta, command line)

I am pleased to announce Hoogle 4.0, available on Hackage. A couple of things to note:

• This is a release of the command-line version only. It will have identical searching abilities to the web-based version, which I'm about to write.


• It currently only searches the same packages as Hoogle 3 (the final release will search more).


• It currently doesn't support the --info flag as previously described (problems with Haddock, not with Hoogle).

Walkthrough: Installation

If you have cabal-install available, it should be as simple as:

$ cabal update && cabal install hoogle

Otherwise, follow the standard Cabal/Hackage guidelines. Hoogle depends on about 4 packages on Hackage which are not available with a standard GHC install, so these will need to be built.

Walkthrough: A few searches

Here are some example searches. I have used --count=5 to limit the number of results displayed. If you are using a terminal with ANSI escape codes I recommend also passing --color to enable colored output.

$ hoogle map --count=5
Prelude map :: (a -> b) -> [a] -> [b]
Data.ByteString map :: (Word8 -> Word8) -> ByteString -> ByteString
Data.IntMap map :: (a -> b) -> IntMap a -> IntMap b
Data.IntSet map :: (Int -> Int) -> IntSet -> IntSet
Data.List map :: (a -> b) -> [a] -> [b]

$ hoogle "(a -> b) -> [a] -> [b]" --count=5
Prelude map :: (a -> b) -> [a] -> [b]
Data.List map :: (a -> b) -> [a] -> [b]
Control.Parallel.Strategies parMap :: Strategy b -> (a -> b) -> [a] -> [b]
Prelude fmap :: Functor f => (a -> b) -> f a -> f b
Control.Applicative <$> :: Functor f => (a -> b) -> f a -> f b

$ hoogle Data.Map.map --count=5
Data.Map map :: (a -> b) -> Map k a -> Map k b
Data.Map data Map k a
module Data.Map
Data.Map mapAccum :: (a -> b -> (a, c)) -> a -> Map k b -> (a, Map k c)
Data.Map mapAccumWithKey :: (a -> k -> b -> (a, c)) -> a -> Map k b -> (a, Map k c)

$ hoogle "Functor f => (a -> b) -> f a -> f b" --count=5
Prelude fmap :: Functor f => (a -> b) -> f a -> f b
Control.Applicative <$> :: Functor f => (a -> b) -> f a -> f b
Control.Monad fmap :: Functor f => (a -> b) -> f a -> f b
Control.Monad.Instances fmap :: Functor f => (a -> b) -> f a -> f b
Data.Traversable fmapDefault :: Traversable t => (a -> b) -> t a -> t b

How you can help

I've released a command line version of the search to solicit feedback. I'm interested in all comments, but especially ones of the form:

• I prefer the command line version of Hoogle 3 because ...


• When I search for ... I would expect result ... to appear, or to appear above result ...


• I was hoping for the feature ...


• It takes too long when I ...

I'm going to be accumulating Hoogle 4 bugs in my bug tracker, or by email (http://www-users.cs.york.ac.uk/~ndm/contact/) - whichever you find more convenient.

Now I'm going to start work on the Web search :-)