Do datatype checking of enum values defined inside anonymous enumeration types (i.e. enum types defined inside a VAR ... END_VAR daclaration).
IEC 61131-3 Annex F Examples (informative)
This directory contains example code take from:
Annex F of Draft 2nd edition of the IEC 61131-3 standard (1998)
"PROGRAMMABLE CONTROLLERS - PROGRAMMING LANGUAGES"