text: #include <stan/math/fwd/scal.hpp>
  #include <gtest/gtest.h>
  
  TEST(MetaTraitsFwdScal, containsFvar) {
    using stan::contains_fvar;
    using stan::math::fvar;
    EXPECT_TRUE((contains_fvar<fvar<double> >::value));
    EXPECT_TRUE((contains_fvar<double, fvar<double> >::value));
    EXPECT_TRUE((contains_fvar<fvar<fvar<double> > >::value));
    bool temp = contains_fvar<double, double, double, double, double,
                              fvar<fvar<double> > >::value;
    EXPECT_TRUE(temp);
  }
  