""
''
"fo\"o"
'fo\'o'
"foo\
bar"
'foo\
bar'

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

[
	["string", "\"\""],
	["string", "''"],
	["string", "\"fo\\\"o\""],
	["string", "'fo\\'o'"],
	["string", "\"foo\\\r\nbar\""],
	["string", "'foo\\\r\nbar'"]
]

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

Checks for single-quoted and double-quoted strings.