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<H1> 2.6 String Literals</H1>
<DIV Class="Paranum"><FONT SIZE=-2>1</FONT></DIV>
<DIV Class="Normal"> [A <FONT FACE="Arial, Helvetica">string_literal</FONT>
is formed by a sequence of graphic characters (possibly none) enclosed
between two quotation marks used as string brackets. They are used to
represent <FONT FACE="Arial, Helvetica">operator_symbol</FONT>s (see
<A HREF="AA-6-1.html">6.1</A>), values of a string type (see <A HREF="AA-4-2.html">4.2</A>),
and array subaggregates (see <A HREF="AA-4-3-3.html">4.3.3</A>). <A NAME="I1257"></A>]</DIV>
<H4 ALIGN=CENTER>Syntax</H4>
<DIV Class="Paranum"><FONT SIZE=-2>2</FONT></DIV>
<DIV Class="SyntaxIndented"><FONT FACE="Arial, Helvetica">string_literal<A NAME="I1258"></A>
::= </FONT>"{<A NAME="I1259"></A><FONT FACE="Arial, Helvetica">string_element</FONT>}"</DIV>
<DIV Class="Paranum"><FONT SIZE=-2>3</FONT></DIV>
<DIV Class="SyntaxIndented"><FONT FACE="Arial, Helvetica">string_element<A NAME="I1260"></A>
::= </FONT>"" | <I>non_quotation_mark_</I><A NAME="I1261"></A><FONT FACE="Arial, Helvetica">graphic_character</FONT></DIV>
<DIV Class="Paranum"><FONT SIZE=-2>4</FONT></DIV>
<DIV Class="SyntaxIndented">A <FONT FACE="Arial, Helvetica">string_element</FONT>
is either a pair of quotation marks (""), or a single <FONT FACE="Arial, Helvetica">graphic_character</FONT>
other than a quotation mark. </DIV>
<H4 ALIGN=CENTER>Static Semantics</H4>
<DIV Class="Paranum"><FONT SIZE=-2>5</FONT></DIV>
<DIV Class="Normal"> <A NAME="I1262"></A>The <I>sequence of characters</I>
of a <FONT FACE="Arial, Helvetica">string_literal</FONT> is formed from
the sequence of <FONT FACE="Arial, Helvetica">string_element</FONT>s
between the bracketing quotation marks, in the given order, with a <FONT FACE="Arial, Helvetica">string_element</FONT>
that is "" becoming a single quotation mark in the sequence
of characters, and any other <FONT FACE="Arial, Helvetica">string_element</FONT>
being reproduced in the sequence.</DIV>
<DIV Class="Paranum"><FONT SIZE=-2>6</FONT></DIV>
<DIV Class="Normal"> <A NAME="I1263"></A>A <I>null string literal</I>
is a <FONT FACE="Arial, Helvetica">string_literal</FONT> with no <FONT FACE="Arial, Helvetica">string_element</FONT>s
between the quotation marks.</DIV>
<DIV Class="NotesHeader"><FONT SIZE=-1>NOTES</FONT></DIV>
<DIV Class="Paranum"><FONT SIZE=-2>7</FONT></DIV>
<DIV Class="Notes"><FONT SIZE=-1>5 An end of line cannot appear
in a <FONT FACE="Arial, Helvetica">string_literal</FONT>. </FONT></DIV>
<H4 ALIGN=CENTER>Examples</H4>
<DIV Class="Paranum"><FONT SIZE=-2>8</FONT></DIV>
<DIV Class="Normal" Style="margin-bottom: 0.4em"> <I>Examples of string
literals:</I> </DIV>
<DIV Class="Paranum"><FONT SIZE=-2>9</FONT></DIV>
<DIV Class="SyntaxIndented">"Message of the day:"<BR>
<BR>
"" --<I> a null string literal</I><BR>
" " "A" """" --<I> three string literals of length 1</I><BR>
<BR>
"Characters such as $, %, and } are allowed in string literals"</DIV>
<H4 ALIGN=CENTER>Wording Changes from Ada 83</H4>
<DIV Class="Paranum"><FONT SIZE=-2>9.a</FONT></DIV>
<DIV Class="Annotations"><FONT SIZE=-1>The wording has been changed to
be strictly lexical. No mention is made of string or character values,
since <FONT FACE="Arial, Helvetica">string_literal</FONT>s are also used
to represent <FONT FACE="Arial, Helvetica">operator_symbol</FONT>s, which
don't have a defined value.</FONT></DIV>
<DIV Class="Paranum"><FONT SIZE=-2>9.b</FONT></DIV>
<DIV Class="Annotations"><FONT SIZE=-1>The syntax is described differently.
</FONT></DIV>
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