3.11.1 Completions of Declarations
1/1
Declarations sometimes come in two parts.
A
declaration that requires a second part is said to
require completion.
The second part is called the
completion of
the declaration (and of the entity declared), and is either another declaration,
a body, or a
pragma.
A
body is a
body,
an
entry_body,
or a renaming-as-body (see
8.5.4).
Name Resolution Rules
2
A construct that can
be a completion is interpreted as the completion of a prior declaration
only if:
3
- The declaration and the completion
occur immediately within the same declarative region;
4
5
- If the declaration is overloadable,
then the completion either has a type-conformant profile, or is a pragma.
Legality Rules
6
An implicit declaration shall not have a completion.
For any explicit declaration that is specified to
require completion, there shall be a corresponding explicit completion.
7
At most one completion is allowed for a given declaration.
Additional requirements on completions appear where each kind of completion
is defined.
8
A type is
completely defined
at a place that is after its full type definition (if it has one) and
after all of its subcomponent types are completely defined. A type shall
be completely defined before it is frozen (see
13.14
and
7.3).
9
91 Completions are in principle allowed
for any kind of explicit declaration. However, for some kinds of declaration,
the only allowed completion is a
pragma
Import, and implementations are not required to support
pragma
Import for every kind of entity.
10
92 There are rules that prevent premature
uses of declarations that have a corresponding completion. The Elaboration_Checks
of
3.11 prevent such uses at run time for
subprograms, protected operations, tasks, and generic units. The rules
of
13.14, “
Freezing
Rules” prevent, at compile time, premature uses of other entities
such as private types and deferred constants.
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