ghc-hackage-db
Access Hackage's package database via Data.Map
This module provides simple access to the Hackage database by means of 'Data.Map'. Suppose you wanted to implement a utility that queries the set of available versions for a given package, the following program would do the trick:>import qualified Distribution.Hackage.DB as DB>import Distribution.Text ( display )>import System.Environment ( getArgs )>>main :: IO ()>main = do>pkgs<- getArgs>db<- DB.readHackage>let getVersions name = maybe [] DB.keys (DB.lookup name db)>mapM_ (putStrLn . unwords . map display . getVersions) pkgs When run, it would produce the following output:>./a.out containers deepseq cabal-install>0.1.0.0 0.1.0.1 0.2.0.0 0.2.0.1 0.3.0.0 0.4.0.0>1.0.0.0 1.1.0.0 1.1.0.1 1.1.0.2>0.4.0 0.5.0 0.5.1 0.5.2 0.6.0 0.6.2 0.6.4 0.8.0 0.8.2 0.10.0 0.10.2.
BSD-3-Clause