Function test_ref_overload_fun2

dependence/eigen-3.4.0/test/ref.cpp:297–297

int test_ref_overload_fun1(Ref<MatrixXf> )       { return 3; }

int test_ref_overload_fun2(Ref<const MatrixXd> ) { return 4; }
int test_ref_overload_fun2(Ref<const MatrixXf> ) { return 5; }

void test_ref_ambiguous(const Ref<const ArrayXd> &A, Ref<ArrayXd> B)