""
"foo""bar"
"foo %foo% bar $bar$ baz @baz@"
''
'foo''bar'
'foo %foo% bar $bar$ baz @baz@'

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

[
	["string", ["\"\""]],
	["string", ["\"foo\"\"bar\""]],
	["string", [
		"\"foo ",
		["variable", "%foo%"],
		" bar ",
		["variable", "$bar$"],
		" baz ",
		["variable", "@baz@"],
		"\""
	]],
	["string", ["''"]],
	["string", ["'foo''bar'"]],
	["string", [
		"'foo ",
		["variable", "%foo%"],
		" bar ",
		["variable", "$bar$"],
		" baz ",
		["variable", "@baz@"],
		"'"
	]]
]

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

Checks for strings and interpolation.