Re: API for looking-up/retrieving Haddock comments?

On 04/08/2012 08:33, Herbert Valerio Riedel wrote:

Simon Hengel writes:

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I have the following in my .ghci:

-- hoogle integration :def hoogle \q -> return $ ":! hoogle --color=true --count=15 \"" ++ q ++ "\"" :def doc \q -> return $ ":! hoogle --color=true --info \"" ++ q ++ "\""

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thanks, this already looks very promising; there's just a few minor issues I'm a bit dissatisfied with the GHCi integration:

1. it doesn't take into account the currently visible module namespaces that GHCi has currently loaded (as opposed to `:info` and `:type`):

,---- | Prelude> import Data.IntMap | | Prelude Data.IntMap> :info fromList | fromList :: [(Key, a)] -> IntMap a -- Defined in `Data.IntMap' | | Prelude Data.IntMap> :type fromList | fromList :: [(Key, a)] -> IntMap a | | Prelude Data.IntMap> :doc fromList | Searching for: fromList | Data.HashTable fromList :: Eq key => (key -> Int32) -> [(key, val)] -> IO (HashTable key val) | | Convert a list of key/value pairs into a hash table. Equality on keys | is taken from the Eq instance for the key type. | | From package base | fromList :: Eq key => (key -> Int32) -> [(key, val)] -> IO (HashTable key val) | | Prelude Data.IntMap> `----

2. tab-completion (as it works for `:type` and `:doc`) doesn't extend to `:doc`

I guess both items could be improved upon by extending GHCi to provide an additional `:def` facility tailored to Haskell symbols allowing to pass more meta-information (such as package and module information) into the resulting command string... would something like that have any chance of being accepted upstream?

I think it would make more sense to just add :doc to the GHCi front-end, relying on the user having already installed hoogle. We could give a sensible error message if you don't have Hoogle installed. Cheers, Simon