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<H1> 5.8 Goto Statements</H1>
<DIV Class="Paranum"><FONT SIZE=-2>1</FONT></DIV>
<DIV Class="Normal"> [A <FONT FACE="Arial, Helvetica">goto_statement</FONT>
specifies an explicit transfer of control from this <FONT FACE="Arial, Helvetica">statement</FONT>
to a target statement with a given label.] </DIV>
<H4 ALIGN=CENTER>Syntax</H4>
<DIV Class="Paranum"><FONT SIZE=-2>2</FONT></DIV>
<DIV Class="SyntaxIndented"><FONT FACE="Arial, Helvetica">goto_statement<A NAME="I2994"></A>
::= </FONT><B>goto</B> <I>label_</I><A NAME="I2995"></A><FONT FACE="Arial, Helvetica">name</FONT>;</DIV>
<H4 ALIGN=CENTER>Name Resolution Rules</H4>
<DIV Class="Paranum"><FONT SIZE=-2>3</FONT></DIV>
<DIV Class="Normal"> <A NAME="I2996"></A>The <I>label_</I><FONT FACE="Arial, Helvetica">name</FONT>
shall resolve to denote a <FONT FACE="Arial, Helvetica">label</FONT>;
the <FONT FACE="Arial, Helvetica">statement</FONT> with that <FONT FACE="Arial, Helvetica">label</FONT>
is the <I>target statement</I>. </DIV>
<H4 ALIGN=CENTER>Legality Rules</H4>
<DIV Class="Paranum"><FONT SIZE=-2>4</FONT></DIV>
<DIV Class="Normal"> The innermost <FONT FACE="Arial, Helvetica">sequence_of_statements</FONT>
that encloses the target statement shall also enclose the <FONT FACE="Arial, Helvetica">goto_statement</FONT>.
Furthermore, if a <FONT FACE="Arial, Helvetica">goto_statement</FONT>
is enclosed by an <FONT FACE="Arial, Helvetica">accept_statement</FONT>
or a body, then the target statement shall not be outside this enclosing
construct. </DIV>
<DIV Class="Paranum"><FONT SIZE=-2>4.a</FONT></DIV>
<DIV Class="Annotations"><FONT SIZE=-1><B>Ramification: </B>The <FONT FACE="Arial, Helvetica">goto_statement</FONT>
can be a <FONT FACE="Arial, Helvetica">statement</FONT> of an inner <FONT FACE="Arial, Helvetica">sequence_</FONT>.</FONT></DIV>
<DIV Class="Paranum"><FONT SIZE=-2>4.b</FONT></DIV>
<DIV Class="Annotations"><FONT SIZE=-1>It follows from the second rule
that if the target <FONT FACE="Arial, Helvetica">statement</FONT> is
enclosed by such a construct, then the <FONT FACE="Arial, Helvetica">goto_statement</FONT>
cannot be outside. </FONT></DIV>
<H4 ALIGN=CENTER>Dynamic Semantics</H4>
<DIV Class="Paranum"><FONT SIZE=-2>5</FONT></DIV>
<DIV Class="Normal"> <A NAME="I2997"></A>The execution of a <FONT FACE="Arial, Helvetica">goto_statement</FONT>
transfers control to the target statement, completing the execution of
any <FONT FACE="Arial, Helvetica">compound_statement</FONT> that encloses
the <FONT FACE="Arial, Helvetica">goto_statement</FONT> but does not
enclose the target. </DIV>
<DIV Class="NotesHeader"><FONT SIZE=-1>NOTES</FONT></DIV>
<DIV Class="Paranum"><FONT SIZE=-2>6</FONT></DIV>
<DIV Class="Notes"><FONT SIZE=-1>10 The above rules allow
transfer of control to a <FONT FACE="Arial, Helvetica">statement</FONT>
of an enclosing <FONT FACE="Arial, Helvetica">sequence_of_statements</FONT>
but not the reverse. Similarly, they prohibit transfers of control such
as between alternatives of a <FONT FACE="Arial, Helvetica">case_statement</FONT>,
<FONT FACE="Arial, Helvetica">if_statement</FONT>, or <FONT FACE="Arial, Helvetica">select_statement</FONT>;
between <FONT FACE="Arial, Helvetica">exception_handler</FONT>s; or from
an <FONT FACE="Arial, Helvetica">exception_handler</FONT> of a <FONT FACE="Arial, Helvetica">handled_sequence_of_statements</FONT>
back to its <FONT FACE="Arial, Helvetica">sequence_of_statements</FONT>.
</FONT></DIV>
<H4 ALIGN=CENTER>Examples</H4>
<DIV Class="Paranum"><FONT SIZE=-2>7</FONT></DIV>
<DIV Class="Normal" Style="margin-bottom: 0.4em"> <I>Example of a
loop containing a goto statement:</I> </DIV>
<DIV Class="Paranum"><FONT SIZE=-2>8</FONT></DIV>
<DIV Class="Examples"><TT><<Sort>><BR>
<B>for</B> I <B>in</B> 1 .. N-1 <B>loop</B><BR>
<B>if</B> A(I) > A(I+1) <B>then</B><BR>
Exchange(A(I), A(I+1));<BR>
<B>goto</B> Sort;<BR>
<B>end</B> <B>if</B>;<BR>
<B>end</B> <B>loop</B>;</TT></DIV>
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