80 /* A symbol table with all values declared for enumerated types declared in global scope

    81  * (i.e. declared inside a TYPE ... END_TYPE declaration.

    82  */

    83 /* Notes:

    84  * (A) - Some enumerations are implicitly declared inside a VAR ... END_VAR declaration

    85  *   (e.g. VAR enum_var : (enumvalue1, enumvalue2); END_VAR)

    86  *   These enumvalueX will only be valid (in scope) inside the POU in which the enum_var is declared. 

    87  *   Because of this, they are not stored in this symbol table

    88  *

    89  * (B) - if the value is defined multiple times the value is the null pointer.

    90  *

    91  * (C) - The stored symbol_c * associated to the value points to the enumerated_type_name

    92  *   (i.e. the name of the enumerated data type) in which the the value/identifier is used/declared.

    93  *

    94  * (D) - We could re-use the null_symbol4 object, but it is safer to use a distinct object

    95  *   (i.e. it might make it easier to find strange bugs).

    96  */

    97 extern symbol_c null_symbol5;

    98 extern symtable_c<symbol_c *, &null_symbol5> enumerated_value_symtable;

    99