DATATYPE-ITEMS ::= datatype-items DATATYPE-DECL+
A list DATATYPE-ITEMS of datatype declarations is written:
types DD1; ... DDn;
The order of the datatype declarations is not significant: there is non-linear visibility of the declared sorts in a list (in contrast to the linear visibility between the BASIC-ITEMS of a BASIC-SPEC, and between the SIG-ITEMS of a SORT-GEN).