8.5.1 Object Renaming Declarations

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An object_renaming_declaration is used to rename an object.


object_renaming_declaration ::= defining_identifier : subtype_mark renames object_name;

Name Resolution Rules

The type of the object_name shall resolve to the type determined by the subtype_mark.

Legality Rules

The renamed entity shall be an object.

The renamed entity shall not be a subcomponent that depends on discriminants of a variable whose nominal subtype is unconstrained, unless this subtype is indefinite, or the variable is aliased. A slice of an array shall not be renamed if this restriction disallows renaming of the array. In addition to the places where Legality Rules normally apply, these rules apply also in the private part of an instance of a generic unit. These rules also apply for a renaming that appears in the body of a generic unit, with the additional requirement that even if the nominal subtype of the variable is indefinite, its type shall not be a descendant of an untagged generic formal derived type.

Static Semantics

An object_renaming_declaration declares a new view of the renamed object whose properties are identical to those of the renamed view. Thus, the properties of the renamed object are not affected by the renaming_declaration. In particular, its value and whether or not it is a constant are unaffected; similarly, the constraints that apply to an object are not affected by renaming (any constraint implied by the subtype_mark of the object_renaming_declaration is ignored).


Example of renaming an object:

    L : Person renames Leftmost_Person; -- see 3.10.1
    L.Age := L.Age + 1;

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