How to use cmdline to send key `<ESC>`?

Question

As title. I need to use this in a script to close the current floating window.

Answer 1

I just resolved this using NeoVIm by the way:

vim.keymap.set({'n', 't'}, '<M-Tab>', function ()
  if (vim.api.nvim_win_get_config(0).relative ~= '') then
    vim.api.nvim_input('<ESC>')
  end
  require('FTerm').toggle()
end, NOREF_NOERR_TRUNC)

Answer 2

In my case I spent a lot of time trying to go back to terminal-normal mode, and this works:

vim.api.nvim_feedkeys('', 't', true)

The invisible part in neovim looks like ^\^N. And to make it work as expected you need to make sure that you don't do any "smart" remapping on neither <C-N> nor <C-\\> in Tmux or Alacritty configs. (I did :()

So to my original question <Esc> looks like ^[, but in one (not two!) char.

Answer 3

There is also :stopinsert, which "works like typing <Esc> in Insert mode."

                            *:stopi* *:stopinsert*
:stopi[nsert]       Stop Insert mode or |Terminal-mode| as soon as
            possible.  Works like typing <Esc> in Insert mode.
            Can be used in an autocommand, example:  
                :au BufEnter scratch stopinsert