When searching for a function on the Hoogle website, one sees the documentation associated with it, e.g.:
mod :: a -> a -> a infixl 7
integer modulus, satisfying
(x `div` y)*y + (x `mod` y) == x
Hoogle also exists as a command line executable. As far as I know, it only shows the signature of the function:
~ ❯❯❯ hoogle --info Prelude.mod
Prelude mod :: Integral a => a -> a -> a
From package base
mod :: Integral a => a -> a -> a
Is there a way to get the associated documentation through the command line, as in the online version?
Use the -i option. It is not obvious how to get help for the default command (search); here is how to do it:
$ hoogle search --help
Hoogle v4.2.41, (C) Neil Mitchell 2004-2012
http://haskell.org/hoogle
hoogle [search] [OPTIONS] [QUERY]
Perform a search
Flags:
-c --colour --color Use colored output (requires ANSI terminal)
-l --link Give URL's for each result
-i --info Give extended information about the first result
-e --exact Match names exactly when searching
-d --databases=DIR Directories to search for databases
-s --start=INT Start displaying results from this point on (1 based)
-n --count=INT Maximum number of results to return
-w --web[=MODE] Operate as a web tool
-r --repeat=INT Run the search multiple times (for benchmarking)
Common flags:
-? --help Display help message
-V --version Print version information
--numeric-version Print just the version number
-v --verbose Loud verbosity
-q --quiet Quiet verbosity