Default (OSX).sublime-keymap

[
  {
    "keys": [
      "alt+minus"
    ],
    "command": "insert",
    "args": {
      "characters": " <- "
    },
    "context": [
      {
        "key": "selector",
        "operator": "equal",
        "operand": "source.r"
      }
    ]
  }, 
    {"keys": ["super+b"], "command": "expand_selection", "args": {"to": "brackets"}},
    {"keys": ["super+f"], "command": "show_panel", "args": {"panel": "replace"}},
    {"keys": ["super+alt+f"], "command": "show_panel", "args": {"panel": "find"}}
]