{""}
{"fo\"obar"}
{''}
{'fo\'obar'}

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

[
	["smarty", [
		["delimiter", "{"],
		["string", "\"\""],
		["delimiter", "}"]
	]],
	["smarty", [
		["delimiter", "{"],
		["string", "\"fo\\\"obar\""],
		["delimiter", "}"]
	]],
	["smarty", [
		["delimiter", "{"],
		["string", "''"],
		["delimiter", "}"]
	]],
	["smarty", [
		["delimiter", "{"],
		["string", "'fo\\'obar'"],
		["delimiter", "}"]
	]]
]

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

Checks for strings.