- (define-variant-constructor RTD (VARIANT FIELD ...))syntax
Defines a constructor for a new variant subtype of RTD. The subtype has the given immutable FIELDs and the constructor initializes all fields of the record.
The variant subtype is sealed and it is opaque iff RTD is opaque. The UID of the subtype is formed by appending the UID of RTD, - and VARIANT.
The record type descriptor of the variant subtype is attached to the constructor VARIANT as extended procedure data.