I disable the following the modes in init.el
;;flycheck-mode
;;flymake-mode
(flycheck-mode nil)
(flymake-mode nil)
(prettify-symbols-mode nil)
However, they did not work as expected.
My emacs.d excluding 'init.el` cloned from purcell/emacs.d: An Emacs configuration bundle with batteries included
the flycheck-mode flymake-mode and prettify-symbols-mode are enabled by defautl.
The above three are of type function, why not working by passing nil to them?