Boost C++ Libraries

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Struct template has_env_var

boost::proto::result_of::has_env_var — Metafunction for computing the return type of proto::has_env_var().

Synopsis

// In header: <boost/proto/transform/env.hpp>

template<typename Env, typename Key> 
struct has_env_var :
   boost::result_of<proto::functional::has_env_var<Key>(Env)>::type
{
};