[haskell] Add history key bindings to haskell ghci repl

This commit adds the C-j, C-k and C-l bindings to haskell's ghci repl, according
to spacemacs conventions.

CHANGELOG.develop

@@ -1907,6 +1907,11 @@ Other:
   (thanks to cjay, CthulhuDen and Magnus Therning)
 - Included =attrap= when =dante= is used (thanks to Pepe Iborra)
 - Added keybinding ~C-c C-z~ for =haskell-interactive-switch= (thanks to ft)
+- Added keybindings to the GHCI REPL:
+  - ~C-j~ switch to next history item
+  - ~C-k~ switch to previous history item
+  - ~C-l~ clear the REPL
+  (thanks to Joscha)
 **** Helm
 - New packages:
   - =helm-ls-git= (thanks to duianto)

layers/+lang/haskell/README.org

@@ -169,7 +169,7 @@ build =ghc-mod=. You can check which version was used by calling
 =ghc-mod --version=.
 
 *** =lsp=
-=lsp= requires an appropriate installation of =hie= to provide the Haskell language server. 
+=lsp= requires an appropriate installation of =hie= to provide the Haskell language server.
 =hie= is built on =ghc-mod=, so many of the same considerations apply.
 
 Enabling the =lsp= backend requires the =lsp= layer to be enabled, and provides access to
@@ -272,6 +272,9 @@ REPL commands are prefixed by ~SPC m s~:
 | ~SPC m s c~ | clear the REPL                                  |
 | ~SPC m s s~ | show and switch to the REPL                     |
 | ~SPC m s S~ | show the REPL without switching to it           |
+| ~C-j~       | switch to next history item                     |
+| ~C-k~       | switch to previous history item                 |
+| ~C-l~       | clear the REPL                                  |
 
 ** Intero REPL
 Intero REPL commands are prefixed by ~SPC m i~:

layers/+lang/haskell/packages.el

@@ -232,6 +232,12 @@
         (interactive)
         (haskell-process-do-type 1))
 
+      ;; repl key bindings
+      (evil-define-key 'insert haskell-interactive-mode-map
+        (kbd "C-j") 'haskell-interactive-mode-history-next
+        (kbd "C-k") 'haskell-interactive-mode-history-previous
+        (kbd "C-l") 'haskell-interactive-mode-clear)
+
       ;; Bind repl
       (spacemacs/register-repl 'haskell
                                'haskell-interactive-switch "haskell")