3.11 Declarative Parts
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A declarative_part contains declarative_items (possibly none).
Syntax
declarative_part ::= {declarative_item}
declarative_item ::= basic_declarative_item | body
basic_declarative_item ::= basic_declaration | aspect_clause | use_clause
body ::= proper_body | body_stub
proper_body ::= subprogram_body | package_body | task_body | protected_body
Dynamic Semantics
The elaboration of a declarative_part consists of the elaboration of the declarative_items, if any, in the order in which they are given in the declarative_part.
An elaborable construct is in the elaborated state after the normal completion of its elaboration. Prior to that, it is not yet elaborated.
For a construct that attempts to use a body, a check (Elaboration_Check) is performed, as follows:
- For a call to a (non-protected) subprogram that has an explicit body, a check is made that the body is already elaborated. This check and the evaluations of any actual parameters of the call are done in an arbitrary order.
- For a call to a protected operation of a protected type (that has a body -- no check is performed if a pragma Import applies to the protected type), a check is made that the protected_body is already elaborated. This check and the evaluations of any actual parameters of the call are done in an arbitrary order.
- For the activation of a task, a check is made by the activator that the task_body is already elaborated. If two or more tasks are being activated together (see 9.2), as the result of the elaboration of a declarative_part or the initialization for the object created by an allocator, this check is done for all of them before activating any of them.
- For the instantiation of a generic unit that has a body, a check is made that this body is already elaborated. This check and the evaluation of any explicit_generic_actual_parameters of the instantiation are done in an arbitrary order.
The exception Program_Error is raised if any of these checks fails.
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