<?xml version="1.0" encoding="utf-8"?>
<!--
  Copyright 2012 Eric Niebler

  Distributed under the Boost
  Software License, Version 1.0. (See accompanying
  file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
  -->
<header name="boost/proto/functional/fusion/at.hpp">
  <para>Includes Proto callable <computeroutput><classname>boost::proto::functional::at</classname></computeroutput>.</para>

  <namespace name="boost">
    <namespace name="proto">
      <namespace name="functional">

        <!-- proto::functional::at -->
        <struct name="at">
          <purpose>A <conceptname>PolymorphicFunctionObject</conceptname> type that invokes the
            <computeroutput>fusion::at()</computeroutput> accessor function on its arguments.</purpose>
          <description>
            <para>
              A <conceptname>PolymorphicFunctionObject</conceptname> type that invokes the
              <computeroutput>fusion::at()</computeroutput> accessor function on its arguments.</para>
          </description>
          <inherit>
            <type><classname>proto::callable</classname></type>
          </inherit>
          <struct-specialization name="result">
            <template>
              <template-type-parameter name="This"/>
              <template-type-parameter name="Seq"/>
              <template-type-parameter name="N"/>
            </template>
            <specialization>
              <template-arg>This(Seq, N)</template-arg>
            </specialization>
            <inherit>
              <type>fusion::result_of::at&lt;
      typename boost::remove_reference&lt;Seq&gt;::type
    , typename boost::remove_const&lt;typename boost::remove_reference&lt;N&gt;::type&gt;::type
  &gt;</type>
            </inherit>
          </struct-specialization>
          <method-group name="public member functions">
            <method name="operator()" cv="const">
              <type>typename fusion::result_of::at&lt; Seq, N &gt;::type</type>
              <template>
                <template-type-parameter name="Seq"/>
                <template-type-parameter name="N"/>
              </template>
              <parameter name="seq">
                <paramtype>Seq &amp;</paramtype>
              </parameter>
              <parameter name="n">
                <paramtype>N const &amp;</paramtype>
              </parameter>
              <returns>
                <para><computeroutput>fusion::at&lt;N&gt;(seq)</computeroutput></para>
              </returns>
            </method>
            <method name="operator()" cv="const">
              <type>typename fusion::result_of::at&lt; Seq const, N &gt;::type</type>
              <template>
                <template-type-parameter name="Seq"/>
                <template-type-parameter name="N"/>
              </template>
              <parameter name="seq">
                <paramtype>Seq const &amp;</paramtype>
              </parameter>
              <parameter name="n">
                <paramtype>N const &amp;</paramtype>
              </parameter>
              <returns>
                <para><computeroutput>fusion::at&lt;N&gt;(seq)</computeroutput></para>
              </returns>
            </method>
          </method-group>
        </struct>

      </namespace>
    </namespace>
  </namespace>
</header>
