---input---
func test() {
    let world = "world"
    let multi = """
    hello
    \(world)
    !
    """
    return multi
}

---tokens---
'func'        Keyword.Declaration
' '           Text.Whitespace
'test'        Name.Function
'('           Punctuation
')'           Punctuation
' '           Text.Whitespace
'{'           Punctuation
'\n'          Text

'    '        Text.Whitespace
'let'         Keyword.Declaration
' '           Text.Whitespace
'world'       Name.Variable
' '           Text.Whitespace
'='           Punctuation
' '           Text.Whitespace
'"'           Literal.String
'world'       Literal.String
'"'           Literal.String
'\n'          Text

'    '        Text.Whitespace
'let'         Keyword.Declaration
' '           Text.Whitespace
'multi'       Name.Variable
' '           Text.Whitespace
'='           Punctuation
' '           Text.Whitespace
'"""'         Literal.String
'\n    hello\n    ' Literal.String
'\\('         Literal.String.Interpol
'world'       Name
')'           Literal.String.Interpol
'\n    !\n    ' Literal.String
'"""'         Literal.String
'\n'          Text

'    '        Text.Whitespace
'return'      Keyword
' '           Text.Whitespace
'multi'       Name
'\n'          Text

'}'           Punctuation
'\n'          Text