EmacsInsert.nvim

Readline motions and deletions in Neovim.

Supported Readline commands

Readline command	RL shortcut	EmacsInsert.nvim function / Vim command
kill-line	C-k	kill_line
backward-kill-line	C-u	backward_kill_line
kill-word	M-d	kill_word
backward-kill-word	M-BS	backward_kill_word
unix-word-rubout	C-w	unix_word_rubout
delete-char	C-d	<Delete>
backward-delete-char	C-h	<BS>
beginning-of-line	C-a	beginning_of_line
back-to-indentation	M-m	back_to_indentation
end-of-line	C-e	end_of_line
forward-word	M-f	forward_word
backward-word	M-b	backward_word
forward-char	C-f	<Right>
backward-char	C-b	<Left>
next-line	C-n	<Down>
previous-line	C-p	<Up>
transpose-chars	C-t	[Ask if desired][issues]
transpose-words	M-t	[Ask if desired][issues]
quoted-insert	C-v	<C-v>
yank (called put in Vim)	C-y	[Ask if desired][issues]
yank-pop	M-y	[Ask if desired][issues]
undo	C-_	[Ask if desired][issues]
upcase-word	M-u	[Ask if desired][issues]
downcase-word	M-l	[Ask if desired][issues]
capitalize-word	M-c	[Ask if desired][issues]

WIP

Emacs command	Emacs shortcut	EmacsInsert.nvim function
backward-paragraph	C-Up	backward_paragraph
forward-paragraph	C-Down	forward_paragraph

References: GNU docs for moving, text, and killing; and Readline on Wikipedia.

Supported Emacs commands

Emacs command	Emacs shortcut	EmacsInsert.nvim function
back-to-indentation	M-m	back_to_indentation

Do-what-I-mean commands

The following functions can be bound like vim.keymap.set('!', '<C-a>', require 'readline'.dwim_beginning_of_line). Inspired by mwim.el.

• dwim_beginning_of_line
  • Cycle the cursor through the following locations:
    • (Used only if the current line is a single-line comment with no other code, for example a line that begins with // in C or JavaScript, with # in Python, or with -- in Lua.) The first character after the comment leader.
    • The first non-whitespace character on the line.
    • Column 0.
  • For example, calling this function repeatedly would move the cursor (|) like this:

        # Hello, wo|rld!
        # |Hello, world!
        |# Hello, world!
    |   # Hello, world!
        # |Hello, world!
    

• dwim_backward_kill_line
  • Similar to dwim_beginning_of_line, but kills instead of moving the cursor, and does not cycle. If the cursor is to the right of the comment leader on an EOL-comment line, kills the comment text left of the cursor, then the comment leader, then the whitespace left of the cursor, then rolls to the previous line.

Configuring word characters

Readline motions that operate a-word-at-a-time (forward-word, etc.) advance the cursor until arriving at a "word character", then advance until arriving at the first non-word character. Deletion-by-word works similarly. The default set of word characters in Readline consists of letters and digits.

What should count as a "word character" can be context-dependent: for example, in C, one may wish to take the word characters to be the alphanumeric characters (abc…zABC…Z0123…9) and the underscore (_) – those characters that can be used in C variable/symbol names.

This plugin allows you to configure what counts as a word character in two ways:

• You can set the buffer variable readline_word_chars to a string consisting of the word characters for the current buffer.
  • readline.alphanum is provided for convenience, and consists of the characters abc…zABC…Z0123…9.
  • For example, vim.b.readline_word_chars = readline.alphanum .. '_-' will cause alphanumerics, hyphens, and underscores to be treated as word characters in the current buffer.
• You can set readline.word_chars.YOUR_FILETYPE = YOUR_STRING.
  • For example, readline.word_chars.bash = readline.alphanum .. '_-' will cause alphanumerics, hyphens, and underscores to be treated as word characters when filetype=bash.
  • The value of vim.b.readline_word_chars takes precedence in a buffer (if it's set).

If neither of the above is set, we fall back to readline.default_word_chars, which you can set to whatever you like, but which by default is equal to 'abc…zABC…Z0123…9'.

Sample configs

Maximal

This config creates Neovim mappings for all of the default Readline text-editing shortcuts, minus ones EmacsInsert.nvim doesn't (yet) have support for, for example transpose-chars and capitalize-word. You can copy-paste this block into your init.lua and delete the mappings you don't want.

local readline = require 'readline'
vim.keymap.set('!', '<C-k>', readline.kill_line)
vim.keymap.set('!', '<C-u>', readline.backward_kill_line)
vim.keymap.set('!', '<M-d>', readline.kill_word)
vim.keymap.set('!', '<M-BS>', readline.backward_kill_word)
vim.keymap.set('!', '<C-w>', readline.unix_word_rubout)
vim.keymap.set('!', '<C-d>', '<Delete>')  -- delete-char
vim.keymap.set('!', '<C-h>', '<BS>')      -- backward-delete-char
vim.keymap.set('!', '<C-a>', readline.beginning_of_line)
vim.keymap.set('!', '<C-e>', readline.end_of_line)
vim.keymap.set('!', '<M-f>', readline.forward_word)
vim.keymap.set('!', '<M-b>', readline.backward_word)
vim.keymap.set('!', '<C-f>', '<Right>') -- forward-char
vim.keymap.set('!', '<C-b>', '<Left>')  -- backward-char
vim.keymap.set('!', '<C-n>', '<Down>')  -- next-line
vim.keymap.set('!', '<C-p>', '<Up>')    -- previous-line

Similar plugins

• vim-rsi
• readline.vim