GDL Quoted Strings
A quoted string begins and ends with the double quotation character ("). Any characters that appear between will be treated literally as part of the quoted string with the following exceptions:
A percent sign plus a double quotation mark (%") is treated as a literal double quotation character (").
A percent sign plus a less than symbol (%<) is treated as a literal less than symbol (<).
A percent sign followed by any other character is treated as a literal percent sign (%).
The less than symbol (<) introduces a HexSubString context.
Quoted strings can appear within a nested context; only the HexSubString context is recognized within a quoted string.