Re: [RFC] anti-coalescing-operator

On Fri, 25 Oct 2019 at 12:21, Rowan Tommins <rowan.collins@gmail.com> wrote: > > On Thu, 24 Oct 2019 at 22:20, Kosit Supanyo <webdevxp.com@gmail.com> wrote: > > > But I think this functionality should be of something like pipeline > > operator: > > > > // send tmp variable to the next expression unconditionally > > $ret = $_SERVER['fname'] |> $user->setName($$); > > // send tmp variable to the next expression only when $_SERVER['fname'] is > > set. > > $ret = $_SERVER['fname'] ?|> $user->setName($$); > > > > Also the syntax like above will be consistent with the proposed > > safe-navigation operators. > > > > > I really like this idea, and it actually makes the pipeline operator itself > feel more useful, too. > > Imagine this chain, where not only might the variable not be set, but it > might not match a user, or the user might have no name: > > $upperCaseUserName = $_GET['user_id'] ?|> User::getById($$) ?-> getName() > ?|> strtoupper($$); > > As well as not needing to repeat the expression each time, as you would > with an "anti-coalesce", "null-safe chain" feels a clearer reading of the > intent here than "if not unset". I like this. It is a bit like a temporary local variable. One limitation is that you only have one such pipe value at a time. E.g. it would not cover this: return isset($a, $b) ? foo($a, $b) : null; or any nested parameters like foo(bar(baz())) where any intermediate value could be null.