26 KiB
Haskell IDE Engine (HIE)
![](https://github.com/haskell/haskell-ide-engine/raw/master/logos/HIE_logo_512.png)
This project aims to be the universal interface to a growing number of Haskell tools, providing a full-featured and easy to query backend for editors and IDEs that require Haskell-specific functionality.
We are currently focusing on using the Language Server Protocol as the interface via which we talk to clients.
- Haskell IDE Engine (HIE)
- Features
- Installation
- Configuration
- Editor Integration
- Docs on hover/completion
- Contributing
- Documentation
- Troubleshooting
- Emacs
- DYLD on macOS
- macOS: Got error while installing GHC 8.6.1 or 8.6.2 - dyld: Library not loaded: /usr/local/opt/gmp/lib/libgmp.10.dylib
- macOS: Got error while processing diagnostics: unable to load package
integer-gmp-1.0.2.0
- cannot satisfy -package-id <package>
- Nix: cabal-helper, No such file or directory
- Liquid Haskell
Features
-
Supports plain GHC projects, cabal projects(sandboxed and non sandboxed) and stack projects
-
Fast due to caching of compile info
-
Uses LSP, so should be easy to integrate with a wide selection of editors
-
Diagnostics via hlint and GHC warnings/errors
-
Code actions and quick fixes via apply-refact
-
Type information and documentation(via haddock) on hover
-
Jump to definition
-
List all top level definitions
-
Highlight references in document
-
Completion
-
Formatting via brittany
-
Renaming via HaRe
-
Add packages to cabal and hpack package files
-
Typo quick fixes
-
Add missing imports (via hsimport)
Installation
Installation with Nix
Follow the instructions at https://github.com/Infinisil/all-hies
Installation on ArchLinux
An haskell-ide-engine package is available on the AUR.
Using Aura:
# aura -A haskell-ide-engine
Installation from source
To install HIE, you need stack version >= 1.7.1.
HIE builds from source code, so there's a couple of extra steps.
Common pre-requirements
stack
must be in your PATHgit
must be in your PATH- Stack local bin directory must be in your PATH. Get it with
stack path --local-bin
Tip: you can quickly check if some command is in your path by running the command. If you receive some meaningful output instead of "command not found"-like message then it means you have the command in PATH.
Linux-specific pre-requirements
On Linux you will need install a couple of extra libraries (for Unicode (ICU) and NCURSES):
Debian/Ubuntu:
sudo apt install libicu-dev libtinfo-dev libgmp-dev
Fedora:
sudo dnf install libicu-devel ncurses-devel
Windows-specific pre-requirements (optional)
In order to avoid problems with long paths on Windows you can do the following:
-
Edit the group policy: set "Enable Win32 long paths" to "Enabled" (Works only for Windows 10).
-
Clone the
haskell-ide-engine
to the root of your logical drive (e.g. toC:\hie
)
Download the source code
git clone https://github.com/haskell/haskell-ide-engine --recurse-submodules
cd haskell-ide-engine
Building
Uses the shake build system for predictable builds.
Note, on first invocation of the build script, a GHC is being installed for execution.
The GHC used for the install.hs
can be adjusted in shake.yaml
by using a different resolver.
Available commands can be seen with:
stack ./install.hs help
Remember, this will take time to download a Stackage-LTS and an appropriate GHC. However, afterwards all commands should work as expected.
Install via cabal
The install-script can be invoked via cabal
instead of stack
with the command
cabal v2-run ./install.hs --project-file install/shake.project <target>
Running the script with cabal on windows requires a cabal version greater or equal to 3.0.0.0
.
Unfortunately, it is still required to have stack
installed so that the install-script can locate the local-bin
directory (on Linux ~/.local/bin
) and copy the hie
binaries to hie-x.y.z
, which is required for the hie-wrapper
to function as expected. There are plans to remove this requirement and let users build hie only with one build tool or another.
For brevity, only the stack
-based commands are presented in the following sections.
Install cabal using stack
Although you can use hie for stack based projects (those which have a stack.yaml
in the project base directory) without having cabal installed, you will need it for cabal based projects (with only a <projectName>.cabal
file or a cabal.project
one in the project base directory).
You can install an appropiate cabal version using stack by running:
stack ./install.hs stack-install-cabal
Install specific GHC Version
Install Nightly (and hoogle docs):
stack ./install.hs hie-8.6.4
stack ./install.hs build-data
Install LTS (and hoogle docs):
stack ./install.hs hie-8.4.4
stack ./install.hs build-data
The Haskell IDE Engine can also be built with cabal new-build
instead of stack build
.
This has the advantage that you can decide how the GHC versions have been installed.
To see what GHC versions are available, the command stack install.hs cabal-ghcs
can be used.
It will list all GHC versions that are on the path and their respective installation directory.
If you think, this list is incomplete, you can try to modify the PATH variable, such that the executables can be found.
Note, that the targets cabal-build
, cabal-build-data
and cabal-build-all
depend on the found GHC versions.
They install Haskell IDE Engine only for the found GHC versions.
An example output is:
> stack install.hs cabal-ghcs
******************************************************************
Found the following GHC paths:
ghc-8.4.4: /opt/bin/ghc-8.4.4
ghc-8.6.2: /opt/bin/ghc-8.6.2
******************************************************************
If your desired ghc has been found, you use it to install Haskell IDE Engine.
stack install.hs cabal-hie-8.4.4
stack install.hs cabal-build-data
To install HIE for all GHC versions that are present on your system, use:
stack ./install.hs cabal-build-all
In general, targets that use cabal
instead of stack
are prefixed with cabal-*
and are identical to their counterpart, except they do not install a GHC if it is missing but fail.
Multiple versions of HIE (optional)
If you installed multiple versions of HIE then you will need to use a wrapper script. Wrapper script will analyze your project, find suitable version of HIE and launch it. Enable it by editing VS Code settings like that:
"languageServerHaskell.useCustomHieWrapper": true,
"languageServerHaskell.useCustomHieWrapperPath": "hie-wrapper",
Configuration
There are some settings that can be configured via a settings.json
file:
{
"languageServerHaskell": {
"hlintOn": Boolean,
"maxNumberOfProblems": Number
"diagnosticsDebounceDuration" : Number
"liquidOn" : Bool (default False)
"completionSnippetsOn" : Bool (default True)
"formatOnImportOn" : Bool (default True)
"formattingProvider" : String (default "brittany",
alternate "floskell")
}
}
- VS Code: These settings will show up in the settings window
- LanguageClient-neovim: Create this file in
$projectdir/.vim/settings.json
or setg:LanguageClient_settingsPath
Editor Integration
Note to editor integrators: there is now a hie-wrapper
executable, which is installed alongside the hie
executable. When this is invoked in the project root directory, it attempts to work out the GHC version used in the project, and then launch the matching hie
executable.
All of the editor integrations assume that you have already installed HIE (see above) and that stack
put the hie
binary in your path (usually ~/.local/bin
on linux and macOS).
Using HIE with VS Code
Install from the VSCode marketplace, or manually from the repository vscode-hie-server.
Using VS Code with Nix
.config/nixpkgs/config.nix
sample:
with import <nixpkgs> {};
let
hie = (import (fetchFromGitHub {
owner="domenkozar";
repo="hie-nix";
rev="e3113da";
sha256="05rkzjvzywsg66iafm84xgjlkf27yfbagrdcb8sc9fd59hrzyiqk";
}) {}).hie84;
in
{
allowUnfree = true;
packageOverrides = pkgs: rec {
vscode = pkgs.vscode.overrideDerivation (old: {
postFixup = ''
wrapProgram $out/bin/code --prefix PATH : ${lib.makeBinPath [hie]}
'';
});
};
}
Using HIE with Sublime Text
- Make sure HIE is installed (see above) and that the directory stack put the
hie
binary in is in your path- (usually
~/.local/bin
on unix)
- (usually
- Install LSP using Package Control
- From Sublime Text, press Command+Shift+P and search for Preferences: LSP Settings
- Paste in these settings. Make sure to change the command path to your
hie
{
"clients": {
"haskell-ide-engine": {
"command": ["hie"],
"scopes": ["source.haskell"],
"syntaxes": ["Packages/Haskell/Haskell.sublime-syntax"],
"languageId": "haskell",
},
},
}
Now open a Haskell project with Sublime Text. You should have these features available to you:
- Errors are underlined in red
- LSP: Show Diagnostics will show a list of hints and errors
- LSP: Format Document will prettify the file
Using HIE with Vim or Neovim
As above, make sure HIE is installed. Then you can use Coc, LanguageClient-neovim or any other vim Langauge server protocol client. Coc is recommend since it is the only complete LSP implementation for Vim and Neovim and offers snippets and floating documentation out of the box.
Coc
Follow Coc's installation instructions,
Then issue :CocConfig
and add the following to your Coc config file.
"languageserver": {
"haskell": {
"command": "hie-wrapper",
"rootPatterns": [
".stack.yaml",
"cabal.config",
"package.yaml"
],
"filetypes": [
"hs",
"lhs",
"haskell"
],
"initializationOptions": {
"languageServerHaskell": {
}
},
}
}
LanguageClient-neovim
vim-plug
If you use vim-plug, then you can do this by e.g.,
including the following line in the Plug section of your init.vim
or ~/.vimrc
:
Plug 'autozimu/LanguageClient-neovim', {
\ 'branch': 'next',
\ 'do': './install.sh'
\ }
and issuing a :PlugInstall
command within Neovim or Vim.
Clone the LanguageClient-neovim repo
As an alternative to using vim-plug shown above, clone LanguageClient-neovim
into ~/.vim/pack/XXX/start/
, where XXX
is just a name for your "plugin suite".
Sample ~/.vimrc
set rtp+=~/.vim/pack/XXX/start/LanguageClient-neovim
let g:LanguageClient_serverCommands = { 'haskell': ['hie-wrapper'] }
You'll probably want to add some mappings for common commands:
nnoremap <F5> :call LanguageClient_contextMenu()<CR>
map <Leader>lk :call LanguageClient#textDocument_hover()<CR>
map <Leader>lg :call LanguageClient#textDocument_definition()<CR>
map <Leader>lr :call LanguageClient#textDocument_rename()<CR>
map <Leader>lf :call LanguageClient#textDocument_formatting()<CR>
map <Leader>lb :call LanguageClient#textDocument_references()<CR>
map <Leader>la :call LanguageClient#textDocument_codeAction()<CR>
map <Leader>ls :call LanguageClient#textDocument_documentSymbol()<CR>
Use Ctrl+xCtrl+o (<C-x><C-o>
) to open up the auto-complete menu,
or for asynchronous auto-completion, follow the setup instructions on
LanguageClient.
If you'd like diagnostics to be highlighted, add a highlight group for ALEError
/ALEWarning
/ALEInfo
,
or customize g:LanguageClient_diagnosticsDisplay
:
hi link ALEError Error
hi Warning term=underline cterm=underline ctermfg=Yellow gui=undercurl guisp=Gold
hi link ALEWarning Warning
hi link ALEInfo SpellCap
If you're finding that the server isn't starting at the correct project root, it may also be helpful to also specify root markers:
let g:LanguageClient_rootMarkers = ['*.cabal', 'stack.yaml']
Using HIE with Atom
Make sure HIE is installed, then install the two Atom packages atom-ide-ui and ide-haskell-hie,
$ apm install language-haskell atom-ide-ui ide-haskell-hie
Using HIE with Emacs
Install HIE along with the following emacs packages:
Make sure to follow the instructions in the README of each of these packages.
Using HIE with Spacemacs
Install HIE, and then add the following to your .spacemacs
config,
(defun dotspacemacs/layers ()
"..."
(setq-default
;; ...
dotspacemacs-configuration-layers
'(
lsp
(haskell :variables ;; Or optionally just haskell without the variables.
haskell-completion-backend 'ghci
haskell-process-type 'stack-ghci)
)
dotspacemacs-additional-packages '(
(lsp-haskell :location (recipe :fetcher github :repo "emacs-lsp/lsp-haskell"))
)
;; ...
))
and then activate lsp-haskell
in your user-config
section,
(defun dotspacemacs/user-config ()
"..."
(setq lsp-haskell-process-path-hie "hie-wrapper")
(require 'lsp-haskell)
(add-hook 'haskell-mode-hook #'lsp)
)
Now you should be able to use HIE in Spacemacs. I still recommend checking out lsp-ui and lsp-mode.
Using HIE with Spacemacs on Nix Based Projects
If you use HIE with spacemacs on nix-built haskell projects, you may want to try out this spacemacs layer. It has installation instructions which includes a nix expression to install everything that hie needs in your environment. It wraps the hie binary calls to use nix-sandbox to find the closest ancestor directory that has nixfiles.
It is still pretty new and may change drastically as the author understands the lsp, lsp-ui, lsp-haskell, hie stack a bit better. PRs and feedback are very welcome on the layer's repo if you find it useful and/or lacking in some way.
Using HIE with Oni
Oni (a Neovim GUI) added built-in support for HIE, using stack, in #1918. If you need to change the configuration for HIE, you can overwrite the following settings in your ~/.config/oni/config.tsx
file (accessible via the command palette and Configuration: Edit User Config
),
export const configuration = {
"language.haskell.languageServer.command": "stack",
"language.haskell.languageServer.arguments": ["exec", "--", "hie"],
"language.haskell.languageServer.rootFiles": [".git"],
"language.haskell.languageServer.configuration": {},
}
Docs on hover/completion
HIE supports fetching docs from haddock on hover. It will fallback on using a hoogle db(generally located in ~/.hoogle on linux) if no haddock documentation is found.
To generate haddock documentation for stack projects:
$ cd your-project-directory
$ stack haddock --keep-going
To enable documentation generation for cabal projects, add the following to your ~/.cabal/config
documentation: True
To generate a hoogle database that hie can use
$ cd haskell-ide-engine
$ stack --stack-yaml=<stack.yaml you used to build hie> exec hoogle generate
Or you can set the environment variable HIE_HOOGLE_DATABASE
to specify a specific database.
Contributing
Planned Features
- Multiproject support
- Project wide references
- Cross project find definition
- New-build support
- HaRe refactorings
- More code actions
- Cross project/dependency Find Definition
- Case splitting, type insertion etc.
This project is not started from scratch:
- See why we should supersede previous tools
- Check the list of existing tools and functionality
- See more other tools and IDEs for inspiration
It's time to join the project!
❤️ Haskell tooling dream is near, we need your help! ❤️
- Register in our google group mailing list.
- Join our IRC channel at
#haskell-ide-engine
onfreenode
. - Fork this repo and hack as much as you can.
- Ask @alanz or @hvr to join the project.
Documentation
All the documentation is in the docs folder at the root of this project.
Architecture
Have a look at
Troubleshooting
Emacs
Parse errors, file state going out of sync
With the lsp-mode
client for Emacs, it seems that the document can very easily get out of sync between, which leads to parse errors being displayed. To fix this, enable full document synchronization with
(setq lsp-document-sync-method 'full)
emacs-direnv
loads environment too late
emacs-direnv
sometimes loads the environment too late, meaning lsp-mode
won't be able to find correct GHC/cabal versions. To fix this, add a direnv update hook after adding the lsp hook for haskell-mode
(meaning the direnv hook is executed first, because hooks are LIFO):
(add-hook 'haskell-mode-hook 'lsp)
(add-hook 'haskell-mode-hook 'direnv-update-environment)
DYLD on macOS
If you hit a problem that looks like can't load .so/.DLL for: libiconv.dylib (dlopen(libiconv.dylib, 5): image not found)
, it means that libraries cannot be found in the library path. We can hint where to look for them and append more paths to DYLD_LIBRARY_PATH
.
export DYLD_LIBRARY_PATH="$DYLD_LIBRARY_PATH:/usr/lib:/usr/local/lib"
On practice /usr/local/lib
is full of dylibs linked by brew
. After you amend DYLD_LIBRARY_PATH
, some of the previously compiled application might not work and yell about incorrect linking, for example, dyld: Symbol not found: __cg_jpeg_resync_to_restart
. You may need to look up where it comes from and remove clashing links, in this case it were clashing images libs:
$ brew unlink libjpeg
$ brew unlink libtiff
$ brew unlink libpng
Recompile.
macOS: Got error while installing GHC 8.6.1 or 8.6.2 - dyld: Library not loaded: /usr/local/opt/gmp/lib/libgmp.10.dylib
These builds have a dependency on homebrew's gmp
library. Install with brew: brew install gmp
.
Should be fixed in GHC 8.6.3.
macOS: Got error while processing diagnostics: unable to load package integer-gmp-1.0.2.0
Rename the file at ~/.stack/programs/x86_64-osx/ghc-8.4.3/lib/ghc-8.4.3/integer-gmp-1.0.2.0/HSinteger-gmp-1.0.2.0.o
to a temporary name.
Should be fixed in GHC 8.8.1.
cannot satisfy -package-id <package>
Is <package> base-x?
Make sure that the GHC version of HIE matches the one of the project. After that run
$ cabal configure
and then restart HIE (e.g. by restarting your editor).
Is there a hash (#) after <package>?
Delete any .ghc.environment*
files in your project root and try again. (At the time of writing, cabal new-style projects are not supported with ghc-mod)
Otherwise
Try running cabal update
.
Nix: cabal-helper, No such file or directory
An error on stderr like
cabal-helper-wrapper: /home/<...>/.cache/cabal-helper/cabal-helper<...>: createProcess: runInteractiveProcess:
exec: does not exist (No such file or directory)
can happen because cabal-helper compiles and runs above executable at runtime without using nix-build, which means a Nix garbage collection can delete the paths it depends on. Delete ~/.cache/cabal-helper and restart HIE to fix this.
Liquid Haskell
Liquid Haskell requires an SMT solver on the path. We do not take care of installing one, thus, Liquid Haskell will not run until one is installed. The recommended SMT solver is z3. To run the tests, it is also required to have an SMT solver on the path, otherwise the tests will fail for Liquid Haskell.