problem setting default variable value

I’m trying to define a record variable and getting the error “&default value has inconsistent type”. The line is:

whitelist_l4_protocol: set[transport_proto] &default=unknown_transport &log;

unknown_transport is one of the values for enum transport_proto. I’ve tried enclosing the value in quotes. I get the same error.

I’ve also tried

whitelist_l4_protocol: set[transport_proto] &default={unknown_transport} &log;

This throws the error “syntax error, at or near “{“.

Please advise!

Best Regards,

Earl Eiland,

Sr. Cyber Security Engineer,

Emerging Technologies, root9B,

San Antonio, Texas