[foo](http://prismjs.com)
![foo](http://prismjs.com "Foo\"bar")
[foo] [bar]

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

[
	["url", [
		"[foo](http://prismjs.com)"
	]],
	["url", [
		"![foo](http://prismjs.com ",
		["string", "\"Foo\\\"bar\""],
		")"
	]],
	["url", [
		"[foo] [",
		["variable", "bar"],
		"]"
	]]
]

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

Checks for URLs.