eglot.el

(use-package haskell-mode
  :ensure t
  :bind (:map haskell-mode-map
		("C-SPC" . 'company-complete)
		("C-q" . 'eldoc-box-help-at-point)))

(use-package company
  :ensure t
  :hook haskell-mode
  :init
  (setq company-idle-delay nil))  ;; dont show company popup during typing

(use-package eglot
  :ensure t
  :config
  (setq eldoc-display-functions (list 'eldoc-display-in-buffer)))

(use-package eldoc-box
  :ensure t
  :custom
  (eldoc-box-clear-with-C-g t))

lsp-mode.el

(use-package haskell-mode
  :ensure t
  :bind (:map haskell-mode-map
		("C-SPC" . 'company-complete)  ;; show company popup
		("C-q" . 'lsp-ui-doc-show)))   ;; show lsp-ui-doc

(use-package lsp-mode
  :ensure t
  :config
  ;; set highlight font
  (set-face-attribute 'lsp-face-highlight-textual nil :weight 'bold :foreground nil :background nil))

(use-package lsp-ui
  :ensure t
  :init
  (setq lsp-ui-doc-position 'at-point)
  (setq lsp-ui-doc-show-with-mouse nil)
  (setq lsp-ui-doc-use-webkit nil))

(use-package lsp-haskell
  :ensure t)
  
(add-hook 'haskell-mode-hook #'lsp)

(use-package company
  :ensure t
  :hook haskell-mode
  :init
  (setq company-idle-delay nil))  ;; dont show company popup during typing