hie-lsp

Building

With GHC 8.8

$ cabal new-configure -w <ghc-8.8> --allow-newer
$ cabal new-install

Features

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• References
• World's most annoying popup message

Usage

Go the directory of a some cabal project and run:

$ cd some-project-dir
$ cabal new-configure -w <ghc-8.8> --write-ghc-environment-file=always --ghc-options="-fwrite-ide-info"

hie-lsp needs an environment file to pick up your local packages and construct a module graph.

Now, you need to generate a database with hiedb for hie-lsp to work.

The database needs to be called hie-lsp.hiedb and needs to exist in the root directory of your project

$ cd hie-lsp/hiedb
$ cabal new-configure -w <ghc-8.8> --allow-newer
$ cabal new-build
$ cabal new-run hiedb -- -D some-project-dir/hie-lsp.hiedb index some-project-dir

With VSCode, install https://github.com/wz1000/vscode-hie-server

In the vscode-hie-server settings, choose the option to use a "Use Custom Hie Wrapper" and set the "Use Custom Hie Wrapper Path" to a script containing:

#!/bin/sh
hie-lsp

Refreshing Info

To refresh the info from which queries are answered, you need to index your project again with hiedb:

$ cabal new-run hiedb -- -D some-project-dir/hie-lsp.hiedb index some-project-dir

For hie-lsp to pick up the changes, make a trivial change to some file, like adding a space, or opening a new file.