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     <H1 CLASS="title">Function Template <CODE>get</CODE></H1>
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   <DT><A href="#overview">Overview</A></DT>
   <DT><A href="#example">Example</A></DT>
   <DT><A href="#headers">Headers</A></DT>
   <DT><A href="#reference">Reference</A></DT>
 </DL>

 <A NAME="overview"></A>
 <H2>Overview</H2>

 <P>
     The function template <CODE>get</CODE> provides a uniform interface for reading a character from a <A HREF="../concepts/source.html">Source</A>, for use in the definitions of new <A HREF="../guide/concepts.html#filter_concepts">Filter</A> types (<I>see</I> <A HREF="#example">Example</A>).
 </P>

 <A NAME="example"></A>
 <H2>Example</H2>

 <P>
     The following code illustrates the use of the function <CODE>get</CODE> in the definition of an <A HREF="../concepts/input_filter.html">InputFilter</A>.
 </P>

 <PRE CLASS="broken_ie">    <SPAN CLASS="preprocessor">#include</SPAN> <SPAN CLASS="literal">&lt;ctype.h&gt;</SPAN>                        <SPAN CLASS="comment">// tolower</SPAN>
     <SPAN CLASS="preprocessor">#include</SPAN> <A CLASS="header" HREF="../../../../boost/iostreams/concepts.hpp"><SPAN CLASS="literal">&lt;boost/iostreams/concepts.hpp&gt;</SPAN></A>   <SPAN CLASS="comment">// input_filter</SPAN>
     <SPAN CLASS="preprocessor">#include</SPAN> <A CLASS="header" HREF="../../../../boost/iostreams/operations.hpp"><SPAN CLASS="literal">&lt;boost/iostreams/operations.hpp&gt;</SPAN></A> <SPAN CLASS="comment">// get, EOF, WOULD_BLOCK</SPAN>

     <SPAN CLASS="keyword">using</SPAN> <SPAN CLASS="keyword">namespace</SPAN> std;
     <SPAN CLASS="keyword">using</SPAN> <SPAN CLASS="keyword">namespace</SPAN> boost::io;

     <SPAN CLASS="keyword">struct</SPAN> tolower_filter : <SPAN CLASS="keyword">public</SPAN> input_filter {
         <SPAN CLASS="keyword">template</SPAN>&lt;<SPAN CLASS="keyword">typename</SPAN> Source&gt;
         <SPAN CLASS="keyword">int</SPAN> get(Source& src)
         {
             <SPAN CLASS="keyword">int</SPAN> c;
             <SPAN CLASS="keyword">return</SPAN> (c == boost::iostreams::get(src)) != <SPAN CLASS='numeric_literal'>EOF</SPAN> &amp;&amp;
                     c != WOULD_BLOCK
                         ?
                 tolower((<SPAN CLASS="keyword">unsigned</SPAN> <SPAN CLASS="keyword">char</SPAN>) c) :
                 c;
         }
     };</PRE>

 <A NAME="headers"></A>
 <H2>Headers</H2>

 <DL>
   <DT><A CLASS="header" HREF="../../../../boost/iostreams/get.hpp"><CODE>&lt;boost/iostreams/get.hpp&gt;</CODE></A></DT>
   <DT><A CLASS="header" HREF="../../../../boost/iostreams/operations.hpp"><CODE>&lt;boost/iostreams/operations.hpp&gt;</CODE></A></DT>
 </DL>

 <A NAME="reference"></A>
 <H2>Reference</H2>

 <A NAME="description"></A>
 <H4>Description</H4>

 <P>Attemps to extract a character from a given instance of the template parameter <CODE>Source</CODE>, returning the extracted character or one of the special values <CODE>traits_type::eof</CODE> or <A HREF="../classes/char_traits.html#would_block"><CODE>traits_type::would_block</CODE></A>, where <CODE>traits_type</CODE> is an appropriate specialization of <A HREF="../classes/char_traits.html"><CODE>boost::iostreams::char_traits</CODE></A></P>

 <A NAME="synopsis"></A>
 <H4>Synopsis</H4>

 <PRE CLASS="broken_ie"><SPAN CLASS="keyword">namespace</SPAN> boost { <SPAN CLASS="keyword">namespace</SPAN> iostreams {

     <SPAN CLASS="keyword">template</SPAN>&lt;<SPAN CLASS="keyword">typename</SPAN> <A CLASS="documented" HREF="#template_params">Source</A>&gt;
     <SPAN CLASS="keyword">typename</SPAN> <A CLASS='documented' HREF="../guide/traits.html#int_type_of_ref">int_type_of</A>&lt;Source&gt;::type
     <A CLASS="documented" HREF="#semantics">get</A>(<A CLASS="documented" HREF="#template_params">Source</A>& <A CLASS="documented" HREF="#function_params">src</A>);

 } } <SPAN CLASS="comment">// End namespace boost::io</SPAN></PRE>

 <A NAME="template_params"></A>
 <H4>Template Parameters</H4>

 <TABLE STYLE="margin-left:2em" BORDER=0 CELLPADDING=2>
 <TR>
     <TR>
         <TD VALIGN="top"><I>Source</I></TD><TD WIDTH="2em" VALIGN="top">-</TD>
         <TD>A model of <A HREF="../concepts/source.html">Source</A>.
     </TR>
 </TABLE>

 <A NAME="function_params"></A>
 <H4>Function Parameters</H4>

 <TABLE STYLE="margin-left:2em" BORDER=0 CELLPADDING=2>
 <TR>
     <TR>
         <TD VALIGN="top"><I>src</I></TD><TD WIDTH="2em" VALIGN="top">-</TD>
         <TD>An instance of <CODE>Source</CODE></TD>
     </TR>
 </TABLE>

 <A NAME="semantics"></A>
 <H4>Semantics</H4>

 <PRE CLASS="broken_ie">    <SPAN CLASS="keyword">template</SPAN>&lt;<SPAN CLASS="keyword">typename</SPAN> Source&gt;
     <SPAN CLASS="keyword">typename</SPAN> int_type_of&lt;Source&gt;::type
     get(Source& src);</PRE>

 <P>The semantics of <CODE>get</CODE> depends on the <A HREF="../guide/traits.html#category">category</A> of <CODE>Source</CODE> as follows:</P>

 <TABLE STYLE="margin:0,0,2em,2em" BORDER=1 CELLPADDING=4>
     <TR><TH><CODE>category_of&lt;Source&gt;::type</CODE></TH><TH>semantics</TH></TR>
     <TR>
         <TD VALIGN="top">convertible to <A HREF="../guide/traits.html#category_tags"><CODE>direct_tag</CODE></A></TD>
         <TD>compile-time error</CODE></TD>
     </TR>
     <TR>
         <TD VALIGN="top">convertible to <A HREF="../guide/traits.html#category_tags"><CODE>istream_tag</CODE></A></TD>
         <TD>returns <CODE>src.get()</CODE></TD>
     </TR>
     <TR>
         <TD VALIGN="top">convertible to <A HREF="../guide/traits.html#category_tags"><CODE>streambuf_tag</CODE></A> but not to <A HREF="../guide/traits.html#category_tags"><CODE>istream_tag</CODE></A></TD>
         <TD>returns <CODE>src.sbumpc()</CODE></TD>
     </TR>
     <TR>
         <TD VALIGN="top">otherwise</TD>
         <TD>
             attempts to extract a single character using <CODE>src.read()</CODE>, returning the extracted character if successful and one of the special values <CODE>traits_type::eof</CODE> or <A HREF="../classes/char_traits.html#would_block"><CODE>traits_type::would_block</CODE></A> otherwise, where <CODE>traits_type</CODE> is <A HREF="../classes/char_traits.html"><CODE>boost::iostreams::char_traits&lt;Source&gt;</CODE></A>
         </TD>
     </TR>
 </TABLE>

 <!-- Begin Footer -->

 <HR>
 <P CLASS="copyright">Revised 02 Feb 2008</P>

 <P CLASS="copyright">&copy; Copyright 2008 <a href="http://www.coderage.com/" target="_top">CodeRage, LLC</a><br/>&copy; Copyright 2004-2007 <a href="http://www.coderage.com/turkanis/" target="_top">Jonathan Turkanis</a></P>
 <P CLASS="copyright">
     Distributed under the Boost Software License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at <A HREF="http://www.boost.org/LICENSE_1_0.txt">http://www.boost.org/LICENSE_1_0.txt</A>)
 </P>

 <!-- End Footer -->

 </BODY>
	<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
	<HTML>
	<HEAD>
	<TITLE>Function Template get</TITLE>
	<LINK REL="stylesheet" HREF="../../../../boost.css">
	<LINK REL="stylesheet" HREF="../theme/iostreams.css">
	</HEAD>
	<BODY>

	<!-- Begin Banner -->

	<H1 CLASS="title">Function Template <CODE>get</CODE></H1>
	<HR CLASS="banner">

	<!-- End Banner -->

	<DL class="page-index">
	<DT><A href="#overview">Overview</A></DT>
	<DT><A href="#example">Example</A></DT>
	<DT><A href="#headers">Headers</A></DT>
	<DT><A href="#reference">Reference</A></DT>
	</DL>

	<A NAME="overview"></A>
	<H2>Overview</H2>

	<P>
	The function template <CODE>get</CODE> provides a uniform interface for reading a character from a <A HREF="../concepts/source.html">Source</A>, for use in the definitions of new <A HREF="../guide/concepts.html#filter_concepts">Filter</A> types (<I>see</I> <A HREF="#example">Example</A>).
	</P>

	<A NAME="example"></A>
	<H2>Example</H2>

	<P>
	The following code illustrates the use of the function <CODE>get</CODE> in the definition of an <A HREF="../concepts/input_filter.html">InputFilter</A>.
	</P>

	<PRE CLASS="broken_ie"> <SPAN CLASS="preprocessor">#include</SPAN> <SPAN CLASS="literal"><ctype.h></SPAN> <SPAN CLASS="comment">// tolower</SPAN>
	<SPAN CLASS="preprocessor">#include</SPAN> <A CLASS="header" HREF="../../../../boost/iostreams/concepts.hpp"><SPAN CLASS="literal"><boost/iostreams/concepts.hpp></SPAN></A> <SPAN CLASS="comment">// input_filter</SPAN>
	<SPAN CLASS="preprocessor">#include</SPAN> <A CLASS="header" HREF="../../../../boost/iostreams/operations.hpp"><SPAN CLASS="literal"><boost/iostreams/operations.hpp></SPAN></A> <SPAN CLASS="comment">// get, EOF, WOULD_BLOCK</SPAN>

	<SPAN CLASS="keyword">using</SPAN> <SPAN CLASS="keyword">namespace</SPAN> std;
	<SPAN CLASS="keyword">using</SPAN> <SPAN CLASS="keyword">namespace</SPAN> boost::io;

	<SPAN CLASS="keyword">struct</SPAN> tolower_filter : <SPAN CLASS="keyword">public</SPAN> input_filter {
	<SPAN CLASS="keyword">template</SPAN><<SPAN CLASS="keyword">typename</SPAN> Source>
	<SPAN CLASS="keyword">int</SPAN> get(Source& src)
	{
	<SPAN CLASS="keyword">int</SPAN> c;
	<SPAN CLASS="keyword">return</SPAN> (c == boost::iostreams::get(src)) != <SPAN CLASS='numeric_literal'>EOF</SPAN> &&
	c != WOULD_BLOCK
	?
	tolower((<SPAN CLASS="keyword">unsigned</SPAN> <SPAN CLASS="keyword">char</SPAN>) c) :
	c;
	}
	};</PRE>

	<A NAME="headers"></A>
	<H2>Headers</H2>

	<DL>
	<DT><A CLASS="header" HREF="../../../../boost/iostreams/get.hpp"><CODE><boost/iostreams/get.hpp></CODE></A></DT>
	<DT><A CLASS="header" HREF="../../../../boost/iostreams/operations.hpp"><CODE><boost/iostreams/operations.hpp></CODE></A></DT>
	</DL>

	<A NAME="reference"></A>
	<H2>Reference</H2>

	<A NAME="description"></A>
	<H4>Description</H4>

	<P>Attemps to extract a character from a given instance of the template parameter <CODE>Source</CODE>, returning the extracted character or one of the special values <CODE>traits_type::eof</CODE> or <A HREF="../classes/char_traits.html#would_block"><CODE>traits_type::would_block</CODE></A>, where <CODE>traits_type</CODE> is an appropriate specialization of <A HREF="../classes/char_traits.html"><CODE>boost::iostreams::char_traits</CODE></A></P>

	<A NAME="synopsis"></A>
	<H4>Synopsis</H4>

	<PRE CLASS="broken_ie"><SPAN CLASS="keyword">namespace</SPAN> boost { <SPAN CLASS="keyword">namespace</SPAN> iostreams {

	<SPAN CLASS="keyword">template</SPAN><<SPAN CLASS="keyword">typename</SPAN> <A CLASS="documented" HREF="#template_params">Source</A>>
	<SPAN CLASS="keyword">typename</SPAN> <A CLASS='documented' HREF="../guide/traits.html#int_type_of_ref">int_type_of</A><Source>::type
	<A CLASS="documented" HREF="#semantics">get</A>(<A CLASS="documented" HREF="#template_params">Source</A>& <A CLASS="documented" HREF="#function_params">src</A>);

	} } <SPAN CLASS="comment">// End namespace boost::io</SPAN></PRE>

	<A NAME="template_params"></A>
	<H4>Template Parameters</H4>

	<TABLE STYLE="margin-left:2em" BORDER=0 CELLPADDING=2>
	<TR>
	<TR>
	<TD VALIGN="top"><I>Source</I></TD><TD WIDTH="2em" VALIGN="top">-</TD>
	<TD>A model of <A HREF="../concepts/source.html">Source</A>.
	</TR>
	</TABLE>

	<A NAME="function_params"></A>
	<H4>Function Parameters</H4>

	<TABLE STYLE="margin-left:2em" BORDER=0 CELLPADDING=2>
	<TR>
	<TR>
	<TD VALIGN="top"><I>src</I></TD><TD WIDTH="2em" VALIGN="top">-</TD>
	<TD>An instance of <CODE>Source</CODE></TD>
	</TR>
	</TABLE>

	<A NAME="semantics"></A>
	<H4>Semantics</H4>

	<PRE CLASS="broken_ie"> <SPAN CLASS="keyword">template</SPAN><<SPAN CLASS="keyword">typename</SPAN> Source>
	<SPAN CLASS="keyword">typename</SPAN> int_type_of<Source>::type
	get(Source& src);</PRE>

	<P>The semantics of <CODE>get</CODE> depends on the <A HREF="../guide/traits.html#category">category</A> of <CODE>Source</CODE> as follows:</P>

	<TABLE STYLE="margin:0,0,2em,2em" BORDER=1 CELLPADDING=4>
	<TR><TH><CODE>category_of<Source>::type</CODE></TH><TH>semantics</TH></TR>
	<TR>
	<TD VALIGN="top">convertible to <A HREF="../guide/traits.html#category_tags"><CODE>direct_tag</CODE></A></TD>
	<TD>compile-time error</CODE></TD>
	</TR>
	<TR>
	<TD VALIGN="top">convertible to <A HREF="../guide/traits.html#category_tags"><CODE>istream_tag</CODE></A></TD>
	<TD>returns <CODE>src.get()</CODE></TD>
	</TR>
	<TR>
	<TD VALIGN="top">convertible to <A HREF="../guide/traits.html#category_tags"><CODE>streambuf_tag</CODE></A> but not to <A HREF="../guide/traits.html#category_tags"><CODE>istream_tag</CODE></A></TD>
	<TD>returns <CODE>src.sbumpc()</CODE></TD>
	</TR>
	<TR>
	<TD VALIGN="top">otherwise</TD>
	<TD>
	attempts to extract a single character using <CODE>src.read()</CODE>, returning the extracted character if successful and one of the special values <CODE>traits_type::eof</CODE> or <A HREF="../classes/char_traits.html#would_block"><CODE>traits_type::would_block</CODE></A> otherwise, where <CODE>traits_type</CODE> is <A HREF="../classes/char_traits.html"><CODE>boost::iostreams::char_traits<Source></CODE></A>
	</TD>
	</TR>
	</TABLE>

	<!-- Begin Footer -->

	<HR>
	<P CLASS="copyright">Revised 02 Feb 2008</P>

	<P CLASS="copyright">© Copyright 2008 <a href="http://www.coderage.com/" target="_top">CodeRage, LLC</a><br/>© Copyright 2004-2007 <a href="http://www.coderage.com/turkanis/" target="_top">Jonathan Turkanis</a></P>
	<P CLASS="copyright">
	Distributed under the Boost Software License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at <A HREF="http://www.boost.org/LICENSE_1_0.txt">http://www.boost.org/LICENSE_1_0.txt</A>)
	</P>

	<!-- End Footer -->

	</BODY>