" href="../../proto/reference.html#header.boost.proto.transform.env_hpp" title="Header &lt;boost/proto/transform/env.hpp&gt;">boost/proto/transform/env.hpp</a>&gt;

</span>
<span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">typename</span> Key<span class="special">,</span> <span class="keyword">typename</span> Env<span class="special">&gt;</span> 
  <span class="keyword">typename</span> <a class="link" href="result_of/env_var.html" title="Struct template env_var">pro