Enumeration data type in ST language into Arduino PLC IDE

Development Tools PLC IDE
1

Hello everyone...
I have problems with definition of new enumeration data type into PLC IDE.
I'd like to define a custom myEnumType datatype, than define a global variable as MyVar: = myEnumType;

Where I can write the follow enumeration data type definition?

TYPE
myEnumType:
(
      A	:= 0,
      B
);
END_TYPE

Thank you in advance