NOTE: v1.0.0 introduces some backward incompatible changes. Please review the docs.

We're coming down to the ground

There's no better place to go

(Peter Gabriel)

Can't stand the dozen of MB of YouCompleteMe? Can't figure out the correct settings to tame NeoComplete? D'you think AutoComplPop is an old fashioned fusion group and Supertab a movie hero for children?

With less code than documentation, µcomplete may be the minimalistic autocompletion plugin you were looking for!

MUcomplete is an implementation of chained (fallback) completion, whereby several completion methods are attempted one after another until a result is returned. MUcomplete brings Vim completion down to earth again.

Under the hood, µcomplete does nothing more than typing some completion mappings for you, either when you press <tab>/<s-tab> or automatically while you are typing. You choose which completion methods to use and in which order, and µcomplete does the rest. It does no caching, no asynchronous computation, no intelligent guessing. It just makes use of core Vim features.

MUcomplete requires Vim 7.2 compiled with +insert_expand and +menu. Automatic completion works in Vim 7.4.775 or later (Vim 7.4.784 or later recommended). MUcomplete is developed and tested on Vim 8. NeoVim is supported, too.

Installation does not require anything special. If you need help, please read How to Install.

Mandatory Vim settings:

  set completeopt+=menuone

For automatic completion, you also need to put at least one of the following in your vimrc (choose the combination that best fits your taste):

  set completeopt+=noselect
  set completeopt+=noinsert

Other recommended settings:

  set shortmess+=c   " Shut off completion messages
  set belloff+=ctrlg " If Vim beeps during completion

No other configuration is needed. Just start pressing <tab> or <s-tab> to complete a word. If you want to enable automatic completion at startup, put

let g:mucomplete#enable_auto_at_startup = 1

in your .vimrc. Automatic completion may be enabled and disabled at any time with :MUcompleteAutoToggle.

When the pop-up menu is visible, you may cycle back and forth through the completion methods in the current completion chain by pressing <c-h> and <c-j>, respectively. See below for an example.

MUcomplete is fully customizable. See :help mucomplete.txt for detailed documentation.

Important: by itself, µcomplete does not provide any “intellisense”/semantic completion. If you want that, you also need to install suitable omni completion plugins for the languages you are using (see the examples below).

The first example shows µcomplete automatically offering suggestions from jedi-vim, which provides semantic completion for Python. Used settings:

set noshowmode shortmess+=c
set completeopt-=preview
set completeopt+=longest,menuone,noinsert,noselect
let g:jedi#popup_on_dot = 0  " It may be 1 as well
let g:mucomplete#enable_auto_at_startup = 1

The second example shows how different completion methods (omni completion, keyword completion, file completion) are automatically selected in different contexts. Used settings:

set showmode shortmess-=c
set completeopt+=menuone,noinsert,noselect
let g:mucomplete#user_mappings = { 'sqla' : "\<c-c>a" }
let g:mucomplete#chains = { 'sql' : ['file', 'sqla', 'keyn'] }
let g:mucomplete#enable_auto_at_startup = 1

The example above shows µcomplete used with clang-complete. You may also see how it is possible to switch between different completion methods (omni completion and keyword completion in this case) when the pop-up menu is visible, using <c-j> and <c-h> (pay attention when lo is completed). Relevant settings:

set noshowmode shortmess+=c
set noinfercase
set completeopt-=preview
set completeopt+=menuone,noinsert,noselect
" The following line assumes `brew install llvm` in macOS
let g:clang_library_path = '/usr/local/opt/llvm/lib/libclang.dylib'
let g:clang_user_options = '-std=c++14'
let g:clang_complete_auto = 1
let g:mucomplete#enable_auto_at_startup = 1

See :help mucomplete-compatibility.

See :help mucomplete-troubleshooting.