haskell

Haskell Layer

This layer provides support for the Haskell language with the following packages:

• neovimhaskell/haskell-vim
• vmchale/cabal-project-vim
• vmchale/ghci-syntax
• Twinside/vim-hoogle
• mpickering/hlint-refactor-vim
• eagletmt/neco-ghc
• Shougo/vimproc.vim'
• parsonsmatt/intero-neovim
• owickstrom/neovim-ghci
• eagletmt/ghcmod-vim
• `ndmitchell/ghcid'

Table of Contents

• Install
  • Binaries
  • Completion
  • Checkers
• Key Bindings
  • REPL
  • Navigation
  • Refactor
  • Documentation
  • Backend

Install

Add the +lang/haskell layer in your configuration file,

function! Layers()
  " ...
  Layer '+lang/haskell'
  " ...
endfunction

The available backends are:

• lsp
• ghc-mod
• intero (default)
• both

You can change it to intero etc with let g:spHaskellBackend 'intero' in your UserInit. The backend called both will try to enable both intero and ghc-mod in a compatible way.

To enable type info on hover (i.e. holding the cursor for ~1 second), put let g:spHaskellTypeOnHover = 1 in your UserInit.

Binaries

To utilize this layer you need ghc-mod, hlint and apply-refact on your path. This can be done with,

$ stack install ghcid hlint

Indentation

You can configure the indentation by setting g:sp_haskell_indentation in your user-init block (i.e. before loading the plugin). By default it is set to 2.

Completion

By default g:necoghc_enable_detailed_browse is enabled. It can be disabled by setting g:sp_necoghc_enable_detailed_browse to either 1 or 0.

Checkers

By default g:neomake_haskell_enabled_makers is set to use all makers. This can be overwritten by setting the desired makers with g:sp_neomake_haskell_enabled_makers.

Key Bindings

Key Binding	Description
SPC m d	Ghcid

REPL

With ghc-mod backend enabled,

Key Binding	Description
SPC m s b	Load current buffer into repl
SPC m s S	Jump to repl
SPC m s s	Open repl
SPC m s H	Hide repl
SPC m s r	Reload the repl
SPC m s e	Evaluate expression in the repl

With intero backend enabled,

Key Binding	Description
SPC m s b	Load current buffer into repl
SPC m s S	Jump to repl
SPC m s s	Open repl
SPC m s H	Hide repl
SPC m s r	Reload the repl

Navigation

With intero or lsp backend enabled,

Key Binding	Description
SPC m g g	Go to definition

Refactor

Key Binding	Description
SPC m r r	Apply Hlint refector suggestion at point
SPC m r b	Apply all Hlint refactor suggestions

Additionally some commands depend on the backend. With ghc-mod,

Key Binding	Description
SPC m r f	Split the function case by examining a type's constructors
SPC m r g	Insert initial code from the given signature
SPC m r e	You can see the expansion of splices

Additionally some commands depend on the backend. With lsp,

Key Binding	Description
SPC m r R	Rename the item under the cursor

Documentation

Key Binding	Description
SPC m h h	Start a Hoogle search query
SPC m h H	Start a Hoogle search query with --info
SPC m h C	Close Hoogle window

Additionally some commands depend on the backend. With ghc-mod,

Key Binding	Description
SPC m h t	Display the type of the identifier under the cursor
SPC m h i	Display the info of the identifier under the cursor
SPC m h T	Insert the type signature of the identifier under the cursor
SPC m h c	Clear ghc-mod type highlights

With intero,

Key Binding	Description
SPC m h t	Display the type of the identifier under the cursor
SPC m h g	Display the generic type of the identifier under the cursor
SPC m h T	Insert the type signature of the identifier under the cursor

Backend

With ghc-mod backend enabled,

Key Binding	Description
SPC m i c	Check file with ghc-mod

With intero backend enabled,

Key Binding	Description
SPC m i d	Reload intero
SPC m i k	Destroy intero
SPC m i r	Start intero
SPC m i t	Set intero targets