Mixed literals are nonnumeric literals that combine single-byte and double-byte characters. Each string of double-byte characters must be delimited by an opening "shift-out" control character (hexadecimal 0E) and a closing "shift-in" control character (hexadecimal 0F), to distinguish it from single-byte data. The control characters are included in the length of the mixed literal. A double-byte character string may consist solely of the two control characters.
COBOL statements process mixed literals without sensitivity to the machine representation. Those statements that operate on a byte-to-byte basis (for example, STRING and UNSTRING) may produce character strings that are not valid mixtures of single-byte and double-byte characters. It is the user's responsibility to be certain that the statements are used correctly.
A mixed literal will only be recognized as such if the program is compiled using the GRAPHIC option of the PROCESS statement; otherwise, it will be treated as a simple non-numeric literal.