Vim settings

.vimrc

" Automatically switch into paste mode when pasting text
let &t_SI .= "\<Esc>[?2004h"
let &t_EI .= "\<Esc>[?2004l"

inoremap <special> <expr> <Esc>[200~ XTermPasteBegin()

function! XTermPasteBegin()
  set pastetoggle=<Esc>[201~
  set paste
  return ""
endfunction

" Manually toggle paste while in insert mode
set pastetoggle=<F2>

" https://stackoverflow.com/questions/1878974/redefine-tab-as-4-spaces

" For tab characters that appear 4-spaces-wide:

" set tabstop=4
" If you're using actual tab character in your source code you probably also want these settings 
" (these are actually the defaults, but you may want to set them defensively):

" set softtabstop=0 noexpandtab
" Finally, if you want an indent to correspond to a single tab, you should also use:

" set shiftwidth=4
" For indents that consist of 4 space characters but are entered with the tab key:

" set tabstop=8 softtabstop=0 expandtab shiftwidth=4 smarttab
" To make the above settings permanent add these lines to your vimrc.

" In case you need to make adjustments, or would simply like to understand what these options all mean,
" here's a breakdown of what each option means:

" tabstop
" The width of a hard tabstop measured in "spaces" -- effectively the (maximum) width of an actual tab character.

" shiftwidth
" The size of an "indent". It's also measured in spaces, so if your code base indents with tab characters then you want
" shiftwidth to equal the number of tab characters times tabstop. This is also used by things like the =, > and < commands.

" softtabstop
" Setting this to a non-zero value other than tabstop will make the tab key (in insert mode) insert a combination of spaces 
" (and possibly tabs) to simulate tab stops at this width.

" expandtab
" Enabling this will make the tab key (in insert mode) insert spaces instead of tab characters. This also affects the behavior
" of the retab command.

" smarttab
" Enabling this will make the tab key (in insert mode) insert spaces or tabs to go to the next indent of the next tabstop when
" the cursor is at the beginning of a line (i.e. the only preceding characters are whitespace).

" For more details on any of these see :help 'optionname' in vim (e.g. :help 'tabstop')