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<div class="section">
<div class="titlepage"><div><div><h5 class="title">
<a name="spirit.qi.reference.char.char"></a><a class="link" href="char.html" title="Char (char_, lit)">Char (<code class="computeroutput"><span class="identifier">char_</span></code>, <code class="computeroutput"><span class="identifier">lit</span></code>)</a>
</h5></div></div></div>
<a name="spirit.qi.reference.char.char.description"></a><h6>
<a name="id878139"></a>
<a class="link" href="char.html#spirit.qi.reference.char.char.description">Description</a>
</h6>
<p>
The <code class="computeroutput"><span class="identifier">char_</span></code> parser matches
single characters. The <code class="computeroutput"><span class="identifier">char_</span></code>
parser has an associated <a class="link" href="../basics.html#spirit.qi.reference.basics.character_encoding_namespace">Character
Encoding Namespace</a>. This is needed when doing basic operations
such as inhibiting case sensitivity and dealing with character ranges.
</p>
<p>
There are various forms of <code class="computeroutput"><span class="identifier">char_</span></code>.
</p>
<a name="spirit.qi.reference.char.char.char_"></a><h6>
<a name="id878185"></a>
<a class="link" href="char.html#spirit.qi.reference.char.char.char_">char_</a>
</h6>
<p>
The no argument form of <code class="computeroutput"><span class="identifier">char_</span></code>
matches any character in the associated <a class="link" href="../basics.html#spirit.qi.reference.basics.character_encoding_namespace">Character
Encoding Namespace</a>.
</p>
<pre class="programlisting"><span class="identifier">char_</span> <span class="comment">// matches any character
</span></pre>
<a name="spirit.qi.reference.char.char.char__ch_"></a><h6>
<a name="id878226"></a>
<a class="link" href="char.html#spirit.qi.reference.char.char.char__ch_">char_(ch)</a>
</h6>
<p>
The single argument form of <code class="computeroutput"><span class="identifier">char_</span></code>
(with a character argument) matches the supplied character.
</p>
<pre class="programlisting"><span class="identifier">char_</span><span class="special">(</span><span class="char">'x'</span><span class="special">)</span> <span class="comment">// matches 'x'
</span><span class="identifier">char_</span><span class="special">(</span><span class="identifier">L</span><span class="char">'x'</span><span class="special">)</span> <span class="comment">// matches L'x'
</span><span class="identifier">char_</span><span class="special">(</span><span class="identifier">x</span><span class="special">)</span> <span class="comment">// matches x (a char)
</span></pre>
<a name="spirit.qi.reference.char.char.char__first__last_"></a><h6>
<a name="id878315"></a>
<a class="link" href="char.html#spirit.qi.reference.char.char.char__first__last_">char_(first,
last)</a>
</h6>
<p>
<code class="computeroutput"><span class="identifier">char_</span></code> with two arguments,
matches a range of characters.
</p>
<pre class="programlisting"><span class="identifier">char_</span><span class="special">(</span><span class="char">'a'</span><span class="special">,</span><span class="char">'z'</span><span class="special">)</span> <span class="comment">// alphabetic characters
</span><span class="identifier">char_</span><span class="special">(</span><span class="identifier">L</span><span class="char">'0'</span><span class="special">,</span><span class="identifier">L</span><span class="char">'9'</span><span class="special">)</span> <span class="comment">// digits
</span></pre>
<p>
A range of characters is created from a low-high character pair. Such
a parser matches a single character that is in the range, including both
endpoints. Note, the first character must be <span class="emphasis"><em>before</em></span>
the second, according to the underlying <a class="link" href="../basics.html#spirit.qi.reference.basics.character_encoding_namespace">Character
Encoding Namespace</a>.
</p>
<p>
Character mapping is inherently platform dependent. It is not guaranteed
in the standard for example that <code class="computeroutput"><span class="char">'A'</span>
<span class="special">&lt;</span> <span class="char">'Z'</span></code>,
that is why in Spirit2, we purposely attach a specific <a class="link" href="../basics.html#spirit.qi.reference.basics.character_encoding_namespace">Character
Encoding Namespace</a> (such as ASCII, ISO-8859-1) to the <code class="computeroutput"><span class="identifier">char_</span></code> parser to eliminate such ambiguities.
</p>
<div class="note"><table border="0" summary="Note">
<tr>
<td rowspan="2" align="center" valign="top" width="25"><img alt="[Note]" src="../../../../images/note.png"></td>
<th align="left">Note</th>
</tr>
<tr><td align="left" valign="top">
<p>
<span class="bold"><strong>Sparse bit vectors</strong></span>
</p>
<p>
To accommodate 16/32 and 64 bit characters, the char-set statically
switches from a <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">bitset</span></code>
implementation when the character type is not greater than 8 bits,
to a sparse bit/boolean set which uses a sorted vector of disjoint
ranges (<code class="computeroutput"><span class="identifier">range_run</span></code>).
The set is constructed from ranges such that adjacent or overlapping
ranges are coalesced.
</p>
<p>
<code class="computeroutput"><span class="identifier">range_runs</span></code> are very
space-economical in situations where there are lots of ranges and a
few individual disjoint values. Searching is O(log n) where n is the
number of ranges.
</p>
</td></tr>
</table></div>
<a name="spirit.qi.reference.char.char.char__def_"></a><h6>
<a name="id878496"></a>
<a class="link" href="char.html#spirit.qi.reference.char.char.char__def_">char_(def)</a>
</h6>
<p>
Lastly, when given a string (a plain C string, a <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">basic_string</span></code>,
etc.), the string is regarded as a char-set definition string following
a syntax that resembles posix style regular expression character sets
(except that double quotes delimit the set elements instead of square
brackets and there is no special negation ^ character). Examples:
</p>
<pre class="programlisting"><span class="identifier">char_</span><span class="special">(</span><span class="string">"a-zA-Z"</span><span class="special">)</span> <span class="comment">// alphabetic characters
</span><span class="identifier">char_</span><span class="special">(</span><span class="string">"0-9a-fA-F"</span><span class="special">)</span> <span class="comment">// hexadecimal characters
</span><span class="identifier">char_</span><span class="special">(</span><span class="string">"actgACTG"</span><span class="special">)</span> <span class="comment">// DNA identifiers
</span><span class="identifier">char_</span><span class="special">(</span><span class="string">"\x7f\x7e"</span><span class="special">)</span> <span class="comment">// Hexadecimal 0x7F and 0x7E
</span></pre>
<a name="spirit.qi.reference.char.char.lit_ch_"></a><h6>
<a name="id878608"></a>
<a class="link" href="char.html#spirit.qi.reference.char.char.lit_ch_">lit(ch)</a>
</h6>
<p>
<code class="computeroutput"><span class="identifier">lit</span></code>, when passed a single
character, behaves like the single argument <code class="computeroutput"><span class="identifier">char_</span></code>
except that <code class="computeroutput"><span class="identifier">lit</span></code> does
not synthesize an attribute. A plain <code class="computeroutput"><span class="keyword">char</span></code>
or <code class="computeroutput"><span class="keyword">wchar_t</span></code> is equivalent
to a <code class="computeroutput"><span class="identifier">lit</span></code>.
</p>
<div class="note"><table border="0" summary="Note">
<tr>
<td rowspan="2" align="center" valign="top" width="25"><img alt="[Note]" src="../../../../images/note.png"></td>
<th align="left">Note</th>
</tr>
<tr><td align="left" valign="top"><p>
<code class="computeroutput"><span class="identifier">lit</span></code> is reused by both
the <a class="link" href="../string/string.html" title="String (string, lit)">string parsers</a>
and the char parsers. In general, a char parser is created when you
pass in a character and a string parser is created when you pass in
a string. The exception is when you pass a single element literal string,
e.g. <code class="computeroutput"><span class="identifier">lit</span><span class="special">(</span><span class="string">"x"</span><span class="special">)</span></code>.
In this case, we optimize this to create a char parser instead of a
string parser.
</p></td></tr>
</table></div>
<p>
Examples:
</p>
<pre class="programlisting"><span class="char">'x'</span>
<span class="identifier">lit</span><span class="special">(</span><span class="char">'x'</span><span class="special">)</span>
<span class="identifier">lit</span><span class="special">(</span><span class="identifier">L</span><span class="char">'x'</span><span class="special">)</span>
<span class="identifier">lit</span><span class="special">(</span><span class="identifier">c</span><span class="special">)</span> <span class="comment">// c is a char
</span></pre>
<a name="spirit.qi.reference.char.char.header"></a><h6>
<a name="id878772"></a>
<a class="link" href="char.html#spirit.qi.reference.char.char.header">Header</a>
</h6>
<pre class="programlisting"><span class="comment">// forwards to &lt;boost/spirit/home/qi/char/char.hpp&gt;
</span><span class="preprocessor">#include</span> <span class="special">&lt;</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">spirit</span><span class="special">/</span><span class="identifier">include</span><span class="special">/</span><span class="identifier">qi_char_</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">&gt;</span>
</pre>
<p>
Also, see <a class="link" href="../../../structure/include.html" title="Include">Include Structure</a>.
</p>
<a name="spirit.qi.reference.char.char.namespace"></a><h6>
<a name="id878846"></a>
<a class="link" href="char.html#spirit.qi.reference.char.char.namespace">Namespace</a>
</h6>
<div class="informaltable"><table class="table">
<colgroup><col></colgroup>
<thead><tr><th>
<p>
Name
</p>
</th></tr></thead>
<tbody>
<tr><td>
<p>
<code class="computeroutput"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">spirit</span><span class="special">::</span><span class="identifier">lit</span> <span class="comment">// alias:
boost::spirit::qi::lit</span></code>
</p>
</td></tr>
<tr><td>
<p>
<code class="computeroutput"><span class="identifier">ns</span><span class="special">::</span><span class="identifier">char_</span></code>
</p>
</td></tr>
</tbody>
</table></div>
<p>
In the table above, <code class="computeroutput"><span class="identifier">ns</span></code>
represents a <a class="link" href="../basics.html#spirit.qi.reference.basics.character_encoding_namespace">Character
Encoding Namespace</a>.
</p>
<a name="spirit.qi.reference.char.char.model_of"></a><h6>
<a name="id878965"></a>
<a class="link" href="char.html#spirit.qi.reference.char.char.model_of">Model of</a>
</h6>
<div class="blockquote"><blockquote class="blockquote"><p>
<a class="link" href="../parser_concepts/primitiveparser.html" title="PrimitiveParser"><code class="computeroutput"><span class="identifier">PrimitiveParser</span></code></a>
</p></blockquote></div>
<div class="variablelist">
<p class="title"><b>Notation</b></p>
<dl>
<dt><span class="term"><code class="computeroutput"><span class="identifier">c</span></code>, <code class="computeroutput"><span class="identifier">f</span></code>, <code class="computeroutput"><span class="identifier">l</span></code></span></dt>
<dd><p>
A literal char, e.g. <code class="computeroutput"><span class="char">'x'</span></code>,
<code class="computeroutput"><span class="identifier">L</span><span class="char">'x'</span></code>
or anything that can be converted to a <code class="computeroutput"><span class="keyword">char</span></code>
or <code class="computeroutput"><span class="keyword">wchar_t</span></code>, or a
<a class="link" href="../basics.html#spirit.qi.reference.basics.lazy_argument">Lazy Argument</a>
that evaluates to anything that can be converted to a <code class="computeroutput"><span class="keyword">char</span></code> or <code class="computeroutput"><span class="keyword">wchar_t</span></code>.
</p></dd>
<dt><span class="term"><code class="computeroutput"><span class="identifier">ns</span></code></span></dt>
<dd><p>
A <a class="link" href="../basics.html#spirit.qi.reference.basics.character_encoding_namespace">Character
Encoding Namespace</a>.
</p></dd>
<dt><span class="term"><code class="computeroutput"><span class="identifier">cs</span></code></span></dt>
<dd><p>
A <a class="link" href="../basics.html#spirit.qi.reference.basics.string">String</a>
or a <a class="link" href="../basics.html#spirit.qi.reference.basics.lazy_argument">Lazy
Argument</a> that evaluates to a <a class="link" href="../basics.html#spirit.qi.reference.basics.string">String</a>
that specifies a char-set definition string following a syntax
that resembles posix style regular expression character sets (except
the square brackets and the negation <code class="computeroutput"><span class="special">^</span></code>
character).
</p></dd>
<dt><span class="term"><code class="computeroutput"><span class="identifier">cp</span></code></span></dt>
<dd><p>
A char parser, a char range parser or a char set parser.
</p></dd>
</dl>
</div>
<a name="spirit.qi.reference.char.char.expression_semantics"></a><h6>
<a name="id879172"></a>
<a class="link" href="char.html#spirit.qi.reference.char.char.expression_semantics">Expression
Semantics</a>
</h6>
<p>
Semantics of an expression is defined only where it differs from, or
is not defined in <a class="link" href="../parser_concepts/primitiveparser.html" title="PrimitiveParser"><code class="computeroutput"><span class="identifier">PrimitiveParser</span></code></a>.
</p>
<div class="informaltable"><table class="table">
<colgroup>
<col>
<col>
</colgroup>
<thead><tr>
<th>
<p>
Expression
</p>
</th>
<th>
<p>
Semantics
</p>
</th>
</tr></thead>
<tbody>
<tr>
<td>
<p>
<code class="computeroutput"><span class="identifier">c</span></code>
</p>
</td>
<td>
<p>
Create char parser from a char, <code class="computeroutput"><span class="identifier">c</span></code>.
</p>
</td>
</tr>
<tr>
<td>
<p>
<code class="computeroutput"><span class="identifier">lit</span><span class="special">(</span><span class="identifier">c</span><span class="special">)</span></code>
</p>
</td>
<td>
<p>
Create a char parser from a char, <code class="computeroutput"><span class="identifier">c</span></code>.
</p>
</td>
</tr>
<tr>
<td>
<p>
<code class="computeroutput"><span class="identifier">ns</span><span class="special">::</span><span class="identifier">char_</span></code>
</p>
</td>
<td>
<p>
Create a char parser that matches any character in the <code class="computeroutput"><span class="identifier">ns</span></code> encoding.
</p>
</td>
</tr>
<tr>
<td>
<p>
<code class="computeroutput"><span class="identifier">ns</span><span class="special">::</span><span class="identifier">char_</span><span class="special">(</span><span class="identifier">c</span><span class="special">)</span></code>
</p>
</td>
<td>
<p>
Create a char parser with <code class="computeroutput"><span class="identifier">ns</span></code>
encoding from a char, <code class="computeroutput"><span class="identifier">c</span></code>.
</p>
</td>
</tr>
<tr>
<td>
<p>
<code class="computeroutput"><span class="identifier">ns</span><span class="special">::</span><span class="identifier">char_</span><span class="special">(</span><span class="identifier">f</span><span class="special">,</span>
<span class="identifier">l</span><span class="special">)</span></code>
</p>
</td>
<td>
<p>
Create a char-range parser that matches characters from range
(<code class="computeroutput"><span class="identifier">f</span></code> to <code class="computeroutput"><span class="identifier">l</span></code>, inclusive) with <code class="computeroutput"><span class="identifier">ns</span></code> encoding.
</p>
</td>
</tr>
<tr>
<td>
<p>
<code class="computeroutput"><span class="identifier">ns</span><span class="special">::</span><span class="identifier">char_</span><span class="special">(</span><span class="identifier">cs</span><span class="special">)</span></code>
</p>
</td>
<td>
<p>
Create a char-set parser with <code class="computeroutput"><span class="identifier">ns</span></code>
encoding from a char-set definition string, <code class="computeroutput"><span class="identifier">cs</span></code>.
</p>
</td>
</tr>
<tr>
<td>
<p>
<code class="computeroutput"><span class="special">~</span><span class="identifier">cp</span></code>
</p>
</td>
<td>
<p>
Negate <code class="computeroutput"><span class="identifier">cp</span></code>.
The result is a negated char parser that matches any character
in the <code class="computeroutput"><span class="identifier">ns</span></code> encoding
except the characters matched by <code class="computeroutput"><span class="identifier">cp</span></code>.
</p>
</td>
</tr>
</tbody>
</table></div>
<a name="spirit.qi.reference.char.char.attributes"></a><h6>
<a name="id879589"></a>
<a class="link" href="char.html#spirit.qi.reference.char.char.attributes">Attributes</a>
</h6>
<div class="informaltable"><table class="table">
<colgroup>
<col>
<col>
</colgroup>
<thead><tr>
<th>
<p>
Expression
</p>
</th>
<th>
<p>
Attribute
</p>
</th>
</tr></thead>
<tbody>
<tr>
<td>
<p>
<code class="computeroutput"><span class="identifier">c</span></code>
</p>
</td>
<td>
<p>
<code class="computeroutput"><span class="identifier">unused</span></code> or if
<code class="computeroutput"><span class="identifier">c</span></code> is a <a class="link" href="../basics.html#spirit.qi.reference.basics.lazy_argument">Lazy Argument</a>,
the character type returned by invoking it.
</p>
</td>
</tr>
<tr>
<td>
<p>
<code class="computeroutput"><span class="identifier">lit</span><span class="special">(</span><span class="identifier">c</span><span class="special">)</span></code>
</p>
</td>
<td>
<p>
<code class="computeroutput"><span class="identifier">unused</span></code> or if
<code class="computeroutput"><span class="identifier">c</span></code> is a <a class="link" href="../basics.html#spirit.qi.reference.basics.lazy_argument">Lazy Argument</a>,
the character type returned by invoking it.
</p>
</td>
</tr>
<tr>
<td>
<p>
<code class="computeroutput"><span class="identifier">ns</span><span class="special">::</span><span class="identifier">char_</span></code>
</p>
</td>
<td>
<p>
The character type of the <a class="link" href="../basics.html#spirit.qi.reference.basics.character_encoding_namespace">Character
Encoding Namespace</a>, <code class="computeroutput"><span class="identifier">ns</span></code>.
</p>
</td>
</tr>
<tr>
<td>
<p>
<code class="computeroutput"><span class="identifier">ns</span><span class="special">::</span><span class="identifier">char_</span><span class="special">(</span><span class="identifier">c</span><span class="special">)</span></code>
</p>
</td>
<td>
<p>
The character type of the <a class="link" href="../basics.html#spirit.qi.reference.basics.character_encoding_namespace">Character
Encoding Namespace</a>, <code class="computeroutput"><span class="identifier">ns</span></code>.
</p>
</td>
</tr>
<tr>
<td>
<p>
<code class="computeroutput"><span class="identifier">ns</span><span class="special">::</span><span class="identifier">char_</span><span class="special">(</span><span class="identifier">f</span><span class="special">,</span>
<span class="identifier">l</span><span class="special">)</span></code>
</p>
</td>
<td>
<p>
The character type of the <a class="link" href="../basics.html#spirit.qi.reference.basics.character_encoding_namespace">Character
Encoding Namespace</a>, <code class="computeroutput"><span class="identifier">ns</span></code>.
</p>
</td>
</tr>
<tr>
<td>
<p>
<code class="computeroutput"><span class="identifier">ns</span><span class="special">::</span><span class="identifier">char_</span><span class="special">(</span><span class="identifier">cs</span><span class="special">)</span></code>
</p>
</td>
<td>
<p>
The character type of the <a class="link" href="../basics.html#spirit.qi.reference.basics.character_encoding_namespace">Character
Encoding Namespace</a>, <code class="computeroutput"><span class="identifier">ns</span></code>.
</p>
</td>
</tr>
<tr>
<td>
<p>
<code class="computeroutput"><span class="special">~</span><span class="identifier">cp</span></code>
</p>
</td>
<td>
<p>
The attribute of <code class="computeroutput"><span class="identifier">cp</span></code>.
</p>
</td>
</tr>
</tbody>
</table></div>
<a name="spirit.qi.reference.char.char.complexity"></a><h6>
<a name="id879991"></a>
<a class="link" href="char.html#spirit.qi.reference.char.char.complexity">Complexity</a>
</h6>
<div class="blockquote"><blockquote class="blockquote"><p>
<span class="bold"><strong>O(N)</strong></span>, except for char-sets with 16-bit
(or more) characters (e.g. <code class="computeroutput"><span class="keyword">wchar_t</span></code>).
These have <span class="bold"><strong>O(log N)</strong></span> complexity, where
N is the number of distinct character ranges in the set.
</p></blockquote></div>
<a name="spirit.qi.reference.char.char.example"></a><h6>
<a name="id880028"></a>
<a class="link" href="char.html#spirit.qi.reference.char.char.example">Example</a>
</h6>
<div class="note"><table border="0" summary="Note">
<tr>
<td rowspan="2" align="center" valign="top" width="25"><img alt="[Note]" src="../../../../images/note.png"></td>
<th align="left">Note</th>
</tr>
<tr><td align="left" valign="top"><p>
The test harness for the example(s) below is presented in the <a class="link" href="../basics.html#spirit.qi.reference.basics.examples">Basics Examples</a>
section.
</p></td></tr>
</table></div>
<p>
Some using declarations:
</p>
<p>
</p>
<pre class="programlisting"><span class="keyword">using</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">spirit</span><span class="special">::</span><span class="identifier">qi</span><span class="special">::</span><span class="identifier">lit</span><span class="special">;</span>
<span class="keyword">using</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">spirit</span><span class="special">::</span><span class="identifier">ascii</span><span class="special">::</span><span class="identifier">char_</span><span class="special">;</span>
</pre>
<p>
</p>
<p>
Basic literals:
</p>
<p>
</p>
<pre class="programlisting"><span class="identifier">test_parser</span><span class="special">(</span><span class="string">"x"</span><span class="special">,</span> <span class="char">'x'</span><span class="special">);</span> <span class="comment">// plain literal
</span><span class="identifier">test_parser</span><span class="special">(</span><span class="string">"x"</span><span class="special">,</span> <span class="identifier">lit</span><span class="special">(</span><span class="char">'x'</span><span class="special">));</span> <span class="comment">// explicit literal
</span><span class="identifier">test_parser</span><span class="special">(</span><span class="string">"x"</span><span class="special">,</span> <span class="identifier">char_</span><span class="special">(</span><span class="char">'x'</span><span class="special">));</span> <span class="comment">// ascii::char_
</span></pre>
<p>
</p>
<p>
Range:
</p>
<p>
</p>
<pre class="programlisting"><span class="keyword">char</span> <span class="identifier">ch</span><span class="special">;</span>
<span class="identifier">test_parser_attr</span><span class="special">(</span><span class="string">"5"</span><span class="special">,</span> <span class="identifier">char_</span><span class="special">(</span><span class="char">'0'</span><span class="special">,</span><span class="char">'9'</span><span class="special">),</span> <span class="identifier">ch</span><span class="special">);</span> <span class="comment">// ascii::char_ range
</span><span class="identifier">std</span><span class="special">::</span><span class="identifier">cout</span> <span class="special">&lt;&lt;</span> <span class="identifier">ch</span> <span class="special">&lt;&lt;</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">endl</span><span class="special">;</span> <span class="comment">// prints '5'
</span></pre>
<p>
</p>
<p>
Character set:
</p>
<p>
</p>
<pre class="programlisting"><span class="identifier">test_parser_attr</span><span class="special">(</span><span class="string">"5"</span><span class="special">,</span> <span class="identifier">char_</span><span class="special">(</span><span class="string">"0-9"</span><span class="special">),</span> <span class="identifier">ch</span><span class="special">);</span> <span class="comment">// ascii::char_ set
</span><span class="identifier">std</span><span class="special">::</span><span class="identifier">cout</span> <span class="special">&lt;&lt;</span> <span class="identifier">ch</span> <span class="special">&lt;&lt;</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">endl</span><span class="special">;</span> <span class="comment">// prints '5'
</span></pre>
<p>
</p>
<p>
Lazy char_ using <a href="../../../../../../phoenix/doc/html/index.html" target="_top">Phoenix</a>
</p>
<p>
</p>
<pre class="programlisting"><span class="keyword">namespace</span> <span class="identifier">phx</span> <span class="special">=</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">phoenix</span><span class="special">;</span>
<span class="identifier">test_parser</span><span class="special">(</span><span class="string">"x"</span><span class="special">,</span> <span class="identifier">phx</span><span class="special">::</span><span class="identifier">val</span><span class="special">(</span><span class="char">'x'</span><span class="special">));</span> <span class="comment">// direct
</span><span class="identifier">test_parser</span><span class="special">(</span><span class="string">"5"</span><span class="special">,</span>
<span class="identifier">char_</span><span class="special">(</span><span class="identifier">phx</span><span class="special">::</span><span class="identifier">val</span><span class="special">(</span><span class="char">'0'</span><span class="special">),</span><span class="identifier">phx</span><span class="special">::</span><span class="identifier">val</span><span class="special">(</span><span class="char">'9'</span><span class="special">)));</span> <span class="comment">// ascii::char_ range
</span></pre>
<p>
</p>
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Distributed under the Boost Software License, Version 1.0. (See accompanying
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