Why my dot key doesn't work properly in insert mode?

Question

I have installed plugins YouCompleteMe and python-mode so as to use the auto-completion when editing a python file. But when I open an .py file and type . in insert mode, the cursor does not move forward as it does in any other case. Then I type a letter and it appears before the dot, which makes auto-completion unavailable.

Actually this question https://stackoverflow.com/questions/33432688/why-dot-is-not-working-properly-in-insert-mode-of-vim-editor is the same as mine. However I don't know how to tell my situation in this question, neither do I know how to send an email to the user who answered the question.

By following the answer to the question mentioned above I can not fix the problem on my computer:

When I type the command

imap .

it shows

i  .           *@.<C-R>=pymode#rope#complete_on_dot()<CR>
    Last set from ~/.vim/bundle/python-mode/ftplugin/python/pymode.vim

When I run the command

iunmap .

it just says

E31: No such mapping

Can anybody help me?

Answer 1

For anyone else stumbling upon this; the reason why :iunmap didn't work is found in :help E31:

- If the mapping is buffer-local you need to use ":unmap <buffer>".

YouCompleteMe seems to just set everything buffer-locally (after all, why shouldn't it?).

When vim throws an error message like E31: No such mapping, you should always take a peek at the relevant help number. They're extremely helpful.

Answer 2

I copied a .vimrc file to my computer from another computer where the auto-completion works. It turned out that .vimrc works on my computer, so the problem is fixed.

However I have lost my original .vimrc, hence I can not give an explanation.