Method or_else

include/common/expected.hpp:1437–1439

  }

  template <class F> expected constexpr or_else(F &&f) const & {
    return or_else_impl(*this, std::forward<F>(f));
  }

#ifndef TL_EXPECTED_NO_CONSTRR
  template <class F> expected constexpr or_else(F &&f) const && {