node /f(o)"o"[b]?a\/r/
$foo = /foo
bar # baz
/m
$foo = /foo
bar # baz
/ixm
$foo = /@(foo)/

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

[
	["keyword", "node"],
	["regex", ["/f(o)\"o\"[b]?a\\/r/"]],
	["variable", ["$foo"]], ["operator", "="],
	["regex", ["/foo\r\nbar # baz\r\n/m"]],
	["variable", ["$foo"]], ["operator", "="],
	["regex", [
		["extended-regex", [
			"/foo\r\nbar ",
			["comment", "# baz"],
			"\r\n/ixm"
		]]
	]],
	["variable", ["$foo"]], ["operator", "="],
	["regex", ["/@(foo)/"]]
]

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

Checks for regular expressions.
Also checks that extended-regex accept inline comments.