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<H1> 8.5 Renaming Declarations</H1>
<DIV Class="Paranum"><FONT SIZE=-2>1</FONT></DIV>
<DIV Class="Normal"> [A <FONT FACE="Arial, Helvetica">renaming_declaration</FONT>
declares another name for an entity, such as an object, exception, package,
subprogram, entry, or generic unit. Alternatively, a <FONT FACE="Arial, Helvetica">subprogram_renaming_declaration</FONT>
can be the completion of a previous <FONT FACE="Arial, Helvetica">subprogram_declaration</FONT>.]
</DIV>
<H4 ALIGN=CENTER>Syntax</H4>
<DIV Class="Paranum"><FONT SIZE=-2>2</FONT></DIV>
<DIV Class="SyntaxIndented"><FONT FACE="Arial, Helvetica">renaming_declaration<A NAME="I3392"></A>
::= </FONT><BR>
<A NAME="I3393"></A><FONT FACE="Arial, Helvetica">object_renaming_declaration</FONT><BR>
| <A NAME="I3394"></A><FONT FACE="Arial, Helvetica">exception_renaming_declaration</FONT><BR>
| <A NAME="I3395"></A><FONT FACE="Arial, Helvetica">package_renaming_declaration</FONT><BR>
| <A NAME="I3396"></A><FONT FACE="Arial, Helvetica">subprogram_renaming_declaration</FONT><BR>
| <A NAME="I3397"></A><FONT FACE="Arial, Helvetica">generic_renaming_declaration</FONT></DIV>
<H4 ALIGN=CENTER>Dynamic Semantics</H4>
<DIV Class="Paranum"><FONT SIZE=-2>3</FONT></DIV>
<DIV Class="Normal"> <A NAME="I3398"></A>The elaboration of a <FONT FACE="Arial, Helvetica">renaming_declaration</FONT>
evaluates the <FONT FACE="Arial, Helvetica">name</FONT> that follows
the reserved word <B>renames</B> and thereby determines the view and
entity denoted by this name <A NAME="I3399"></A><A NAME="I3400"></A>(the
<I>renamed view</I> and <I>renamed entity</I>). [A <FONT FACE="Arial, Helvetica">name</FONT>
that denotes the <FONT FACE="Arial, Helvetica">renaming_declaration</FONT>
denotes (a new view of) the renamed entity.] </DIV>
<DIV Class="NotesHeader"><FONT SIZE=-1>NOTES</FONT></DIV>
<DIV Class="Paranum"><FONT SIZE=-2>4</FONT></DIV>
<DIV Class="Notes"><FONT SIZE=-1>8 Renaming may be used to
resolve name conflicts and to act as a shorthand. Renaming with a different
<FONT FACE="Arial, Helvetica">identifier</FONT> or <FONT FACE="Arial, Helvetica">operator_symbol</FONT>
does not hide the old <FONT FACE="Arial, Helvetica">name</FONT>; the
new <FONT FACE="Arial, Helvetica">name</FONT> and the old <FONT FACE="Arial, Helvetica">name</FONT>
need not be visible at the same places.</FONT></DIV>
<DIV Class="Paranum"><FONT SIZE=-2>5</FONT></DIV>
<DIV Class="Notes"><FONT SIZE=-1>9 A task or protected object
that is declared by an explicit <FONT FACE="Arial, Helvetica">object_declaration</FONT>
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.</FONT></DIV>
<DIV Class="Paranum"><FONT SIZE=-2>6</FONT></DIV>
<DIV Class="Notes" Style="margin-bottom: 0.4em"><FONT SIZE=-1>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 </FONT></DIV>
<DIV Class="Paranum"><FONT SIZE=-2>7</FONT></DIV>
<DIV Class="Examples"><TT> <B>subtype</B> Mode <B>is</B> Ada.Text_IO.File_Mode;</TT></DIV>
<H4 ALIGN=CENTER>Wording Changes from Ada 83</H4>
<DIV Class="Paranum"><FONT SIZE=-2>7.a</FONT></DIV>
<DIV Class="Annotations"><FONT SIZE=-1>The second sentence of RM83-8.5(3),
``At any point where a renaming declaration is visible, the identifier,
or operator symbol of this declaration denotes the renamed entity.''
is incorrect. It doesn't say directly visible. Also, such an <FONT FACE="Arial, Helvetica">identifier</FONT>
might resolve to something else.</FONT></DIV>
<DIV Class="Paranum"><FONT SIZE=-2>7.b</FONT></DIV>
<DIV Class="Annotations"><FONT SIZE=-1>The verbiage about renamings being
legal ``only if exactly one...'', which appears in RM83-8.5(4) (for objects)
and RM83-8.5(7) (for subprograms) is removed, because it follows from
the normal rules about overload resolution. For language lawyers, these
facts are obvious; for programmers, they are irrelevant, since failing
these tests is highly unlikely. </FONT></DIV>
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