J.11 The Class Attribute of Untagged Incomplete Types
Static Semantics
1/2
{
AI95-00326-01}
For the first subtype S of a type T declared
by an incomplete_type_declaration that is
not tagged, the following attribute is defined: 2/2
Denotes the first subtype of the incomplete class-wide
type rooted at T. The completion of T shall declare a tagged
type. Such an attribute reference shall occur in the same library unit
as the incomplete_type_declaration.
2.a/2
Reason: {
AI95-00326-01}
This must occur in the same unit to prevent children
from imposing requirements on their ancestor library units for deferred
incomplete types.
Wording Changes from Ada 95
2.b/2
{
AI95-00326-01}
This clause is new. This feature was moved here
because the tagged incomplete type provides a better way to provide this
capability (it doesn't put requirements on the completion based on uses
that could be anywhere). Pity we didn't think of it in 1994.
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