# ghc-imported-from For a given Haskell source file, determine the path to the Haddock documentation for a symbol at a particular line/col location. Example: on the file [src/Main.hs](https://github.com/carlohamalainen/ghc-imported-from/blob/master/src/Main.hs), ghc-imported-from haddock-url src/Main.hs Main getArgs 160 13 says SUCCESS: file:///home/carlo/opt/ghc-7.6.3_build/share/doc/ghc/html/libraries/base-4.6.0.1/System-Environment.html since the usage of ```getArgs``` at line 160, column 13, is from the ```System.Environment``` module. Difficulties arise because some symbols are exported from a certain package but defined in another, for example ```String``` is defined in ```GHC.Base``` but is exported from the standard prelude, the module ```Prelude```. There are other cases to deal with including qualified imports, selective imports, imports with hidden components, etc. Preference is given to any locally available Haddock documentation, and then to the generic url at hackage.org. ## Beware You may have to run cabal build or cabal repl in a project directory to sort out some of the ```dist/build/autogen``` files. At the moment ```ghc-imported-from``` has no functionality to do this boot process automatically. To run ```cabal repl``` you might need the latest Cabal from [https://github.com/haskell/cabal](https://github.com/haskell/cabal). If you see : cannot satisfy -package hspec (use -v for more information) then you may need the hspec and/or doctest packages: cabal install hspec doctest Feedback and pull requests most welcome! ## Install ### ghc-imported-from Install into ```~/.cabal```: git clone https://github.com/carlohamalainen/ghc-imported-from cd ghc-imported-from cabal install Or, install into a sandbox: git clone https://github.com/carlohamalainen/ghc-imported-from cd ghc-imported-from ./build_in_sandbox.sh Either way, ensure that ```ghc-imported-from``` is in the current PATH. ### ghcimportedfrom-vim Follow the instructions at [https://github.com/carlohamalainen/ghcimportedfrom-vim](https://github.com/carlohamalainen/ghcimportedfrom-vim) to install the Vim plugin. ## Usage See the ```tests``` subdirectory for some examples. Or load your favourite Haskell project and hit F4. Or watch the screencast (be sure to set 720p HD and then fullscreen): [http://www.youtube.com/watch?v=VVc8uupYJGs](http://www.youtube.com/watch?v=VVc8uupYJGs)