foo = function ( x, y) {}
{foo: function () {}}
bar = async function baz (x ) {}
baz = async(x) => x
fooBar = x => x
fooBar = ( x, y ) => x
ಠ_ಠ = () => {}
Ƞȡ_҇ = async (ಠ, Ƞ = 2) => {}

----------------------------------------------------

[
	["function-variable", "foo"],
	["operator", "="],
	["keyword", "function"],
	["punctuation", "("],
	["parameter", [
		"x",
		["punctuation", ","],
		" y"
	]],
	["punctuation", ")"],
	["punctuation", "{"],
	["punctuation", "}"],

	["punctuation", "{"],
	["function-variable", "foo"],
	["punctuation", ":"],
	["keyword", "function"],
	["punctuation", "("],
	["punctuation", ")"],
	["punctuation", "{"],
	["punctuation","}"],
	["punctuation","}"],

	["function-variable", "bar"],
	["operator", "="],
	["keyword", "async"],
	["keyword", "function"],
	["function", "baz"],
	["punctuation", "("],
	["parameter", [
		"x"
	]],
	["punctuation", ")"],
	["punctuation", "{"],
	["punctuation", "}"],

	["function-variable", "baz"],
	["operator", "="],
	["keyword", "async"],
	["punctuation", "("],
	["parameter", [
		"x"
	]],
	["punctuation", ")"],
	["operator", "=>"], " x\r\n",

	["function-variable", "fooBar"],
	["operator", "="],
	["parameter", [
		"x"
	]],
	["operator", "=>"], " x\r\n",

	["function-variable", "fooBar"],
	["operator", "="],
	["punctuation", "("],
	["parameter", [
		"x",
		["punctuation", ","],
		" y"
	]],
	["punctuation", ")"],
	["operator", "=>"], " x\r\n",

	["function-variable", "ಠ_ಠ"],
	["operator", "="],
	["punctuation", "("],
	["punctuation", ")"],
	["operator", "=>"],
	["punctuation", "{"],
	["punctuation", "}"],

	["function-variable", "Ƞȡ_҇"],
	["operator", "="],
	["keyword", "async"],
	["punctuation", "("],
	["parameter", [
		"ಠ",
		["punctuation", ","],
		" Ƞ ",
		["operator", "="],
		["number", "2"]
	]],
	["punctuation", ")"],
	["operator", "=>"],
	["punctuation", "{"],
	["punctuation", "}"]
]

----------------------------------------------------

Checks for variables obviously containing functions.