Vim
Contents
vimrc
Initial configuration happens in the vimrc file, located at ~/.vimrc or ~/.vim/vimrc.
GVim looks in ~/_vimrc or ~/vimfiles/vimrc.
Runtime Path
Vim assumes a standard file structure (see below) and searches for configuration files using a runtimepath option.
First, local configuration is loaded from ~/.vim (or ~/viminfo for GVim).
Second, system configuration is loaded from $VIMRUNTIME.
Third, after local configuration in ~/.vim/after (or ~/vimfiles/after for GVim).
To append a path to the default runtimepath option, edit the vimrc file.
execute 'set runtimepath+=' . expand('~/.marslo/.vim/bundle/vundle')
Directory Structure
Vim loads plugins and configurations based on a directory structure. This directory structure can be used in any path on the runtimepath.
The after directory is meant for plugins/configurations that should override previously evaluated plugins/configurations. This is most commonly used to override system configuration with local configuration.
autoload
Libraries should be located in the autoload directory, This directory is searched for vimscript libraries; functions are loaded into memory but not evaluated.
Given a function foo located in autoload/mylib, use:
call mylib#foo()
plugin
Generic plugins should be located in the plugin directory. This directory is searched recursively for vimscript plugins.
filetype.vim, ftdetect, and scripts.vim
Many subsequent processes are determined by the filetype options. This is set through one of the following:
The vimscript filetype.vim is executed first. Typically, this is used only for generic system configuration.
Secondly, the ftdetect directory is searched for a plugin matching the current buffer's file extension. (To clarify: foo.bar would load ftdetect/bar.vim.) These plugins should look like:
autocmd BufNewFile,BufRead *.bar setfiletype foobar
Lastly, scripts.vim is evaluated. Typically, generic local configurations will be done here. This file is ideal for generic filetype detection logic.
This is all skipped if the command :set filetype [...] off was called.
syntax
Configuration for syntax highlighting based on filetype should be located in the syntax directory. Given a set filetype, Vim searches for syntax/<FILETYPE>.vim. This is skipped if the command :syntax off was called.
This is skipped if the command :set filetype [...] off was called.
ftplugin.vim and ftplugin
The vimscript ftplugin.vim is executed first. Typically, this is used only for generic system configuration.
Plugins that should be loaded/evaluated conditionally based on filetype should be located in the ftplugin directory. Given a set filetype, Vim searches for ftplugin/<FILETYPE>.vim.
This is all skipped if the command :set filetype [...] off was called.
indent.vim and indent
The vimscript indent.vim is executed first. Typically, this is used only for generic system configuration.
Configuration for indentation based on filetype should be located in the indent directory. Given a set filetype, Vim searches for indent/<FILETYPE>.vim.
This is all skipped if the command :set filetype [...] off was called.
compiler
Configuration for compilers based on filetype should be located in the compiler directory. Given a set filetype, Vim searches for compiler/<FILETYPE>.vim.
This is skipped if the command :set filetype [...] off was called.
colors
Color scheme plugins mshould be located in the colors directory. When the :colorscheme command is called, this directory is searched for a plugin matching the name. (To clarify: :colorscheme blue would load colors/blue.vim.)
Pathogen
One of the most popular package management solutions for Vim is Pathogen. Pathogen is a short vimscript that searches an additional directory bundle for sub-directories. These sub-directories are added to the runtimepath option between local and system configuration. Each package then can be setup using the above directory structure and integrate into the Vim ecosystem immediately.
Neovim
Neovim follows the XDG standard, and checks for configuration in ${XDG_CONFIG_HOME}/nvim. The standard is also to use ${XDG_CONFIG_HOME}/init.vim instead of a vimrc file.