Keymap.cson config for Atom

keymap.cson

# Your keymap
#
# Atom keymaps work similarly to style sheets. Just as style sheets use
# selectors to apply styles to elements, Atom keymaps use selectors to associate
# keystrokes with events in specific contexts. Unlike style sheets however,
# each selector can only be declared once.
#
# You can create a new keybinding in this file by typing "key" and then hitting
# tab.
#
# Here's an example taken from Atom's built-in keymap:
#
# 'atom-text-editor':
#   'enter': 'editor:newline'
#
# 'atom-workspace':
#   'ctrl-shift-p': 'core:move-up'
#   'ctrl-p': 'core:move-down'
#
# You can find more information about keymaps in these guides:
# * http://flight-manual.atom.io/using-atom/sections/basic-customization/#customizing-keybindings
# * http://flight-manual.atom.io/behind-atom/sections/keymaps-in-depth/
#
# If you're having trouble with your keybindings not working, try the
# Keybinding Resolver: `Cmd+.` on macOS and `Ctrl+.` on other platforms. See the
# Debugging Guide for more information:
# * http://flight-manual.atom.io/hacking-atom/sections/debugging/#check-the-keybindings
#
# This file uses CoffeeScript Object Notation (CSON).
# If you are unfamiliar with CSON, you can read more about it in the
# Atom Flight Manual:
# http://flight-manual.atom.io/using-atom/sections/basic-customization/#configuring-with-cson

'body .native-key-bindings':
  'ctrl-shift-b': 'native!'

'.platform-win32':
  'ctrl-shift-b': 'fuzzy-finder:toggle-buffer-finder'

'atom-text-editor':
  'ctrl-b': 'bracket-matcher:go-to-matching-bracket'
  'alt-r alt-r': 'es-identifier-highlight:renameIdentifier'
  'ctrl-alt-shift-left': 'es-identifier-highlight:prevIdentifier'
  'ctrl-alt-shift-right': 'es-identifier-highlight:nextIdentifier'
  'ctrl-alt-shift-up': 'es-identifier-highlight:jumpToDefinition'
  'ctrl-shift-f2': 'bookmarks:view-all'

'atom-workspace':
  'ctrl-shift-j': 'bottom-dock:toggle'
  'alt-s': 'symbols-tree-view:toggle'
  "ctrl-tab": "tab-switcher:next"
  "ctrl-tab ^ctrl": "unset!"
  "ctrl-shift-tab": "tab-switcher:previous"
  "ctrl-shift-tab ^ctrl": "unset!"
  "cmd-b": "recent-files-fuzzy-finder:toggle-finder"

'atom-text-editor[data-grammar="source gfm"]:not([mini])':
  'ctrl-t': 'toggle-markdown-task:toggle'
  # Other suggested bindings at
  # https://github.com/melke/markdown-folder/blob/master/
  #   README.md#user-content-markdown-folder-package
  'alt-t': 'markdown-folder:toggle'
  'alt-u': 'markdown-folder:unfoldall'

'.enable-pane-item-control-helper.able-to-be-closed':
  'esc': 'package-pane-item-control-helper:close'

"ol.tab-switcher-tab-list":
  "^ctrl": "tab-switcher:select"
  "^shift": "tab-switcher:select"
  "ctrl-up": "tab-switcher:previous"
  "ctrl-down": "tab-switcher:next"
  "ctrl-escape": "tab-switcher:cancel"
  "ctrl-n": "tab-switcher:next"
  "ctrl-p": "tab-switcher:previous"
  "ctrl-w": "tab-switcher:close"
  "ctrl-s": "tab-switcher:save"
  "cmd-shift-left": "tab-switcher:previous"
  "cmd-shift-right": "tab-switcher:next"

what does the ^ do? I don't see it documented anywhere.