assert_equal(`==`, `==`);
assert_not_equal(`<<`, `<`);
assert_equal(`<`>get_arity(), 2);
assert_equal(`+`.get_annotation(), "Multiple method dispatch function wrapper.");
assert_equal(get_arity.get_contained_functions().size(), 0);
assert_equal(get_arity.get_arity(), 1);
assert_equal(get_arity.get_param_types().size(), 2);

auto paramtypes = get_arity.get_param_types();

assert_equal(true, paramtypes[1].bare_equal(Function_type));
