The converse of
Prohibited fields may not occur in any record of the given type.
The usage is:
%prohibit: field1 field2 ... fieldN
The field names are separated by one or more blank characters.
Fields listed in a
%prohibit entry are
forbidden; i.e., no field with this name should be present
in any record of this kind.
Again, records violating this restriction
%prohibit fields can appear in
the same record descriptor.
The set of prohibited fields
is the union of all the entries.
For example, in the following
id are prohibited:
%rec: Entry %prohibit: Id %prohibit: id
One possible use case for prohibited fields arises
when some field name is reserved for some future
For example, if we were organizing a sports competition, we would want
competitors to register before the event.
However a competitor's
result should not and cannot be entered
before the competition takes place.
Initially then, we would change the record
descriptor as follows:
%rec: Contact %mandatory: Name %prohibit: result
At the start of the event, the
%mandatory line can be deleted, to
allow results to be entered.