3.5.3 Boolean Types


Static Semantics

1 {Boolean} There is a predefined enumeration type named Boolean, [declared in the visible part of package Standard]. {False} {True} It has the two enumeration literals False and True ordered with the relation False < True. {boolean type} Any descendant of the predefined type Boolean is called a boolean type. 

1.a Implementation Note: An implementation is not required to support enumeration representation clauses on boolean types that impose an unacceptable implementation burden. See 13.4, “Enumeration Representation Clauses”. However, it is generally straightforward to support representations where False is zero and True is 2**n – 1 for some n.