Hi everybody!
Yesterday I stumbled upon this Tweet by Nikita: https://twitter.com/nikita_ppv/status/1240309838950866946 It answered why this seemingly correct block of code doesn't work: fn() => throw new Exception('nope'); The answer is rather simple. `throw` is a statement, not an expression. However, arrow functions only allow a single expression as their bodies. The obvious solution is to convert `throw` to an expression. This would also allow for the following: $value = $nullableValue ?? throw new InvalidArgumentException(); $value = $falsableValue ?: throw new InvalidArgumentException(); At the moment this is generally done by moving the `throw` into a function: function throwInvalidArgumentException() { throw new InvalidArgumentException(); } $value = $nullableValue ?? throwInvalidArgumentException(); or of course by just using an `if` statement: if ($nullableValue === null) { throw new InvalidArgumentException(); } Neither of those are bad. The new syntax is just slightly more concise. An implementation of the change can be found here: https://github.com/php/php-src/pull/5279 It's also noteworthy that the same feature has semi-recently been added to C# 7.0: https://docs.microsoft.com/en-us/dotnet/csharp/language-reference/keywords/throw#the-throw-expression This has been proposed a handful of times in the internals mailing list but never extensively discussed: https://externals.io/message/49569 (2010) https://externals.io/message/15301 (2005) https://externals.io/message/10553 (2004) Let me know what you think! Also, to actually create the RFC I need RFC karma. Can someone grant me those privileges? My username is ilijatovilo. Thank you!
