hsimport Vim Plugin

vim-hsimport is a Vim plugin that automatically creates import statements for Haskell source files for the symbol/identifier under the cursor.

It can create import statements for the whole module, for only the desired symbol/indentifier and is also able to create qualified module import statements.

It uses hdevtools for its finding of modules with the desired symbol. By using hdevtools it should also support any cabal setting, a cabal sandbox and even stack.

Currently the biggest issue is if and how modules of your current project are considered for the import, please see the issues section.

Features / Vim Commands

HsimportModule imports the whole module of the symbol/identifier under the cursor.

HsimportSymbol imports only the symbol/indentifier under the cursor.

If the symbol/indentifier under the cursor is contained in multiple modules, then a selection dialog will be shown.

If the symbol has a module qualifier e.g. Text.pack, then both commands will create a qualified import for the selected module. If the module Data.Text was selected, then the created import statement will be import qualified Data.Text as Text.

The first call of either command might take several seconds, because hdevtools has to cache all of the modul informations.

Installation

1. Install hsimport, using a cabal sandbox is the recommend way:

    $ mkdir hsimport
    $ cd hsimport
    $ cabal sandbox init
    $ cabal install hsimport
   

   Your hsimport binary is now at hsimport/.cabal-sandbox/bin/hsimport. Ensure that the binary is reachable through your $PATH environment variable.

2. Install hdevtools, using a cabal sandbox is the recommend way:

    $ mkdir hdevtools
    $ cd hdevtools
    $ cabal sandbox init
    $ cabal install hdevtools
   

   Your hdevtools binary is now at hdevtools/.cabal-sandbox/bin/hdevtools. Ensure that the binary is reachable through your $PATH environment variable.

3. Install vim-hsimport. pathogen.vim is the recommended way:

    $ cd ~/.vim/bundle
    $ git clone https://github.com/dan-t/vim-hsimport
   

Configuration

You most likely want to add keybindings for the two available commands into your ~/.vimrc e.g.:

autocmd FileType haskell nmap <silent> <F1> :silent update <bar> HsimportModule<CR>
autocmd FileType haskell nmap <silent> <F2> :silent update <bar> HsimportSymbol<CR>

How the imports are pretty printed and where they're placed can be configured. Please take a look at the README of hsimport.

Issues

Currently the modules for your own project are considered by a quite simple heuristic. The source tree is searched by grep with a regex that should "mostly" match the symbol with data/type definitions and with top level function/operator definitions.

I'm very open for changing this to something more robust. The solution can return false positives, because the real inspection is done by hdevtools, it's just about to reduce the number of source files given to hdevtools and that it's still fast enough to be interactive usable.

Credits

Heavily inspired by vim-hdevtools.