Niall Douglas wrote:
But if I am writing my implementation that way, it is because there is no purpose here to my function returning empty. Else I would implement it differently.
I appreciate that the above is me speaking vaguely from experience and without concrete evidence.
I usually place high value on argument from experience, even if presented without evidence. But in this case, you've cited https://github.com/ned14/boost.afio/blob/master/include/boost/afio/v2.0/deta... which is this: result<file_handle> file_handle::file(file_handle::path_type _path, file_handle::mode _mode, file_handle::creation _creation, file_handle::caching _caching, file_handle::flag flags) noexcept { result<file_handle> ret(file_handle(native_handle_type(), 0, 0, std::move(_path), _caching, flags)); native_handle_type &nativeh = ret.get()._v; BOOST_OUTCOME_TRY(attribs, attribs_from_handle_mode_caching_and_flags(nativeh, _mode, _creation, _caching, flags)); nativeh.behaviour |= native_handle_type::disposition::file; const char *path_ = ret.value()._path.c_str(); nativeh.fd = ::open(path_, attribs, 0x1b0 /*660*/); if(-1 == nativeh.fd) return make_errored_result<file_handle>(errno, last190(ret.value()._path.native())); BOOST_AFIO_LOG_FUNCTION_CALL(nativeh.fd); if(!(flags & flag::disable_safety_unlinks)) { BOOST_OUTCOME_TRYV(ret.value()._fetch_inode()); } if(_creation == creation::truncate && ret.value().are_safety_fsyncs_issued()) fsync(nativeh.fd); return ret; } Now, the first line constructs result<file_handle> ret(file_handle(native_handle_type(), 0, 0, std::move(_path), _caching, flags)); and it's immediately apparent that returning `ret` in this initial state makes no sense. That is, you either need to further initialize it into a valid file_handle, or return an "errored" result. For this reason, I'd think that a style that does file_handle fh(native_handle_type(), 0, 0, std::move(_path), _caching, flags); first, then initializes it appropriately, and as a final step returns it via result<file_handle>, would perhaps make more sense (and also save a number of ret.value() calls).