I'm trying to set up some basic configuration for vim to make it more useful for myself. One of the things I'm trying to do is map shift+tab to a literal tab character, since my vim configuration sets tabs to be expanded with spaces by default. I attempted to map to the tab char using this reference but no dice.
When I try to strike shift+tab whilst insert mode is active, vim outputs a capital Z for about one second, then removes it and drops out of insert mode with a system error beep. I already tested the shift+tab stroke with ^V and it output ^[[Z into vim as described in the reference, so it's not my OS hijacking the keystroke. Not exactly sure what's causing this; input would be appreciated.
My .vimrc:
" Few basic settings first; I like syntax highlighting & line numbers
syntax on
set number
" Some settings with the list option
" I like to see non-printing characters like Tab & CR
set listchars=tab:▸\ ,eol:¬
set list
" Set tab behaviours: 4 spaces wide, expand <Tab> and >> with spaces
set expandtab
set tabstop=4
set softtabstop=4
set shiftwidth=4
" This line maps shift+tab to a literal tab character
" Because I sometimes need a literal tab
set <s-tab>=
The very last line shows the ▸ character in vim when set list
is on