Try to use intero-neovim

after/ftplugin/haskell.vim

@@ -5,7 +5,6 @@ setlocal ts=2 sw=2 expandtab omnifunc=necoghc#omnifunc
 
 let g:haskell_classic_highlighting = 1
 
-let g:ghcmod_hlint_options = ['--ignore=Eta reduce $']
 
 syntax on
 filetype plugin indent on
@@ -14,21 +13,6 @@ filetype plugin indent on
 call CmdAlias('hasktags', '!/home/jule/.cabal/bin/hasktags -c .<CR>')
 
 
-let g:necoghc_enable_detailed_browse = 1
-
-" ALE
-let g:ale_linters = {'haskell':['ghc-mod', 'hdevtools'], 'c':['clang']}
-" let g:ale_fixers = {
-	" \    'go': ['gofmt', 'goimports'],
-	" \}
-let g:ale_haskell_hdevtools_options = "-g '-Wall' -g '-Wno-orphans'"
-
-" neco-ghc
-let g:haskellmode_completion_ghc = 0
-let g:necoghc_enable_detailed_browse = 1
-autocmd FileType haskell setlocal omnifunc=necoghc#omnifunc
-let g:ycm_semantic_triggers = {'haskell' : ['.']}
-
 
 function! HaskellDocCurrentWord()
         let word = expand("<cword>")
@@ -36,17 +20,9 @@ function! HaskellDocCurrentWord()
 endfunction
 
 
-" clear search
-nmap <F2> :noh<CR>:GhcModTypeClear<CR>
-imap <F2> <C-O>:noh<CR>:GhcModTypeClear<CR>
 
-" unmap <F3>
-" unmap <F4>
-
-nmap <F6> :GhcModType<CR>
 nmap <F8> :call HaskellDocCurrentWord()<CR><CR>
 
-
 nmap <silent> <F3> :silent update <bar> HsimportModule<CR>
 nmap <silent> <F4> :silent update <bar> HsimportSymbol<CR>
 
@@ -96,3 +72,56 @@ let g:vim_annotations_offset = '/.liquid/'
 " nnoremap <silent> <F2> :call LanguageClient#textDocument_rename()<CR>
 
 " autocmd VimEnter * LanguageClientStart
+
+if has("nvim")
+	let g:ale_enabled = 0
+
+	let g:intero_backend = {
+			\ 'command': 'cabal new-repl',
+			\ 'options': '',
+			\ 'cwd': expand('%:p:h'),
+			\}
+
+
+	" Intero starts automatically. Set this if you'd like to prevent that.
+	let g:intero_start_immediately = 1
+
+	" Enable type information on hover (when holding cursor at point for ~1 second).
+	let g:intero_type_on_hover = 1
+
+	" Change the intero window size; default is 10.
+	let g:intero_window_size = 15
+
+	" Sets the intero window to split vertically; default is horizontal
+	let g:intero_vertical_split = 1
+
+	" OPTIONAL: Make the update time shorter, so the type info will trigger faster.
+	set updatetime=1000
+
+	map <silent> <leader>t <Plug>InteroGenericType
+else
+	let g:ghcmod_hlint_options = ['--ignore=Eta reduce $']
+
+	" ALE
+	let g:ale_linters = {'haskell':['ghc-mod', 'hdevtools'], 'c':['clang']}
+	" let g:ale_fixers = {
+		" \    'go': ['gofmt', 'goimports'],
+		" \}
+	let g:ale_haskell_hdevtools_options = "-g '-Wall' -g '-Wno-orphans'"
+
+	" neco-ghc
+	let g:necoghc_enable_detailed_browse = 1
+	let g:haskellmode_completion_ghc = 0
+	let g:necoghc_enable_detailed_browse = 1
+	autocmd FileType haskell setlocal omnifunc=necoghc#omnifunc
+	let g:ycm_semantic_triggers = {'haskell' : ['.']}
+
+	" clear search
+	nmap <F2> :noh<CR>:GhcModTypeClear<CR>
+	imap <F2> <C-O>:noh<CR>:GhcModTypeClear<CR>
+
+	" unmap <F3>
+	" unmap <F4>
+
+	nmap <F6> :GhcModType<CR>
+endif

vimrc

@@ -83,8 +83,12 @@ Plug 'Valloric/YouCompleteMe', { 'do': './install.py --clang-completer --go-comp
     \ }
 
 " haskell
-Plug 'eagletmt/ghcmod-vim', { 'for': 'haskell' }
-Plug 'eagletmt/neco-ghc', { 'for': 'haskell' }
+if has("nvim")
+	Plug 'parsonsmatt/intero-neovim'
+else
+	Plug 'eagletmt/ghcmod-vim', { 'for': 'haskell' }
+	Plug 'eagletmt/neco-ghc', { 'for': 'haskell' }
+endif
 Plug 'lukerandall/haskellmode-vim', { 'for': 'haskell' }
 Plug 'raichoo/haskell-vim', { 'for': 'haskell' }
 Plug 'ucsd-progsys/liquid-types.vim', { 'for': 'haskell' }