#8212; A type sequence, for use as the 2<sup>nd</sup> parameter to the
        <code class="computeroutput"><a class="link" href="expr.html" title="Struct template expr">proto::expr&lt;&gt;</a></code> and 
        <code class="computeroutput"><a class="link" href="basic_expr.html" title="Struct template basic_expr">proto::basic_expr&lt;&gt;</a></code>
        class templates.</p>
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<h2 xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" class="refsynopsisdiv-title">Synopsis</h2>
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