I had something like that in my vimrc for some time (snippet posted here: https://vimrcfu.com/snippet/222 https://vimrcfu.com/snippet/222), using omni-completio

I had something like that in my vimrc for some time (snippet posted here: https://vimrcfu.com/snippet/222 https://vimrcfu.com/snippet/222), using omni-completion when set in the buffer and keyword completion otherwise. Then, I developed the idea into a plugin that retains the minimalistic spirit, but it's much more flexible: https://github.com/lifepillar/vim-mucomplete https://github.com/lifepillar/vim-mucomplete.