8.5 Renaming Declarations

From OC Systems Wiki!
< Guide:95lrm
Revision as of 23:38, 4 May 2019 by imported>WikiVisor (1 revision imported)
(diff) ← Older revision | Latest revision (diff) | Newer revision → (diff)
Jump to: navigation, search

A renaming_declaration declares another name for an entity, such as an object, exception, package, subprogram, entry, or generic unit. Alternatively, a subprogram_renaming_declaration can be the completion of a previous subprogram_declaration.

Syntax

renaming_declaration ::=
    object_renaming_declaration
  | exception_renaming_declaration
  | package_renaming_declaration
  | subprogram_renaming_declaration
  | generic_renaming_declaration

Dynamic Semantics

The elaboration of a renaming_declaration evaluates the name that follows the reserved word renames and thereby determines the view and entity denoted by this name (the renamed view and renamed entity). A name that denotes the renaming_declaration denotes (a new view of) the renamed entity.

Notes

8  Renaming may be used to resolve name conflicts and to act as a shorthand. Renaming with a different identifier or operator_symbol does not hide the old name; the new name and the old name need not be visible at the same places.

9  A task or protected object that is declared by an explicit object_declaration can be renamed as an object. However, a single task or protected object cannot be renamed since the corresponding type is anonymous (meaning it has no nameable subtypes). For similar reasons, an object of an anonymous array or access type cannot be renamed.

10  A subtype defined without any additional constraint can be used to achieve the effect of renaming another subtype (including a task or protected subtype) as in

subtype Mode is Ada.Text_IO.File_Mode;

Copyright © 1992,1993,1994,1995 Intermetrics, Inc.
Copyright © 2000 The MITRE Corporation, Inc. Ada Reference Manual