Raw strings are prefixed by a hash ‘#’. Inside them, backslashes and braces are treated like regular characters, so they will not be expanded as macro arguments, interpolated symbols, or escape sequences. For example, the raw string #"\t\1{s}\" is equivalent to the regular string \\t\\1\{s}\\. (Note that this prevents raw strings from including the double quote character.) Raw strings also may be contained in triple quotes for them to be multi-line, so they can include literal newline or quote characters (although still not three quotes in a row).
https://rgbds.gbdev.io/docs/v0.7.0/rgbasm.5#String_expressions