"This $variable is interpolated"
"$foo[2], $bar[-4], $foo[$bar]"
"$foo->bar"
"More {$interpolation}"
"{$arr['key']}, {$arr['foo'][3]}"
"{${$name}}, but not {\${\$name}}"
"the return value of getName(): {${getName()}}"
"the return value of \$object->getName(): {${$object->getName()}}"
"{$foo->$bar}, {$foo->{$baz[1]}}"
<<<FOO
Heredoc strings $also->support {${$string->interpolation()}}
FOO;
<<<"FOO_BAR"
	{${$name}}, but not {\${\$name}}
FOO_BAR;

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

[
	["double-quoted-string", [
		"\"This ",
		["interpolation", [["variable", "$variable"]]],
		" is interpolated\""
	]],
	["double-quoted-string", [
		"\"",
		["interpolation", [["variable", "$foo"], ["punctuation", "["], ["number", "2"], ["punctuation", "]"]]],
		", ",
		["interpolation", [["variable", "$bar"], ["punctuation", "["], ["operator", "-"], ["number", "4"], ["punctuation", "]"]]],
		", ",
		["interpolation", [["variable", "$foo"], ["punctuation", "["], ["variable", "$bar"], ["punctuation", "]"]]],
		"\""
	]],
	["double-quoted-string", [
		"\"",
		["interpolation", [["variable", "$foo"], ["operator", "-"], ["operator", ">"], ["property", "bar"]]],
		"\""
	]],
	["double-quoted-string", [
		"\"More ",
		["interpolation", [["punctuation", "{"], ["variable", "$interpolation"], ["punctuation", "}"]]],
		"\""
	]],
	["double-quoted-string", [
		"\"",
		["interpolation", [
			["punctuation", "{"],
			["variable", "$arr"], ["punctuation", "["], ["single-quoted-string", "'key'"], ["punctuation", "]"],
			["punctuation", "}"]
		]],
		", ",
		["interpolation", [
			["punctuation", "{"],
			["variable", "$arr"],
			["punctuation", "["], ["single-quoted-string", "'foo'"], ["punctuation", "]"],
			["punctuation", "["], ["number", "3"], ["punctuation", "]"],
			["punctuation", "}"]
		]],
		"\""
	]],
	["double-quoted-string", [
		"\"",
		["interpolation", [
			["punctuation", "{"], ["variable", "$"], ["punctuation", "{"],
			["variable", "$name"],
			["punctuation", "}"], ["punctuation", "}"]
		]],
		", but not {\\${\\$name}}\""
	]],
	["double-quoted-string", [
		"\"the return value of getName(): ",
		["interpolation", [
			["punctuation", "{"], ["variable", "$"], ["punctuation", "{"],
			["function", "getName"], ["punctuation", "("], ["punctuation", ")"],
			["punctuation", "}"], ["punctuation", "}"]
		]],
		"\""
	]],
	["double-quoted-string", [
		"\"the return value of \\$object->getName(): ",
		["interpolation", [
			["punctuation", "{"], ["variable", "$"], ["punctuation", "{"],
			["variable", "$object"], ["operator", "-"], ["operator", ">"], ["function", "getName"], ["punctuation", "("], ["punctuation", ")"],
			["punctuation", "}"], ["punctuation", "}"]
		]],
		"\""
	]],
	["double-quoted-string", [
		"\"",
		["interpolation", [
			["punctuation", "{"],
			["variable", "$foo"], ["operator", "-"], ["operator", ">"], ["variable", "$bar"],
			["punctuation", "}"]
		]],
		", ",
		["interpolation", [
			["punctuation", "{"],
			["variable", "$foo"], ["operator", "-"], ["operator", ">"], ["punctuation", "{"],
			["variable", "$baz"], ["punctuation", "["], ["number", "1"], ["punctuation", "]"],
			["punctuation", "}"],
			["punctuation", "}"]
		]],
		"\""
	]],
	["heredoc-string", [
		["delimiter", [
			["punctuation", "<<<"], "FOO"
		]],
		"\r\nHeredoc strings ",
		["interpolation", [
			["variable", "$also"], ["operator", "-"], ["operator", ">"], ["property", "support"]
		]],
		["interpolation", [
			["punctuation", "{"], ["variable", "$"], ["punctuation", "{"],
			["variable", "$string"], ["operator", "-"], ["operator", ">"], ["function", "interpolation"], ["punctuation", "("], ["punctuation", ")"],
			["punctuation", "}"], ["punctuation", "}"]
		]],
		["delimiter", [
			"FOO", ["punctuation", ";"]
		]]
	]],
	["heredoc-string", [
		["delimiter", [
			["punctuation", "<<<\""], "FOO_BAR", ["punctuation", "\""]
		]],
		["interpolation", [
			["punctuation", "{"], ["variable", "$"], ["punctuation", "{"],
			["variable", "$name"],
			["punctuation", "}"], ["punctuation", "}"]
		]],
		", but not {\\${\\$name}}\r\n",
		["delimiter", [
			"FOO_BAR", ["punctuation", ";"]
		]]
	]]
]

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

Checks for interpolation inside strings.