On Sun, Mar 22, 2020 at 5:17 PM Ilija Tovilo <ilija.tov...@me.com> wrote:
> Hi everybody! I hope you’re doing well. > > > > Due to the modest feedback I’d like to move the throw expression RFC to > “under discussion”. > > https://wiki.php.net/rfc/throw_expression > > > > In short, the RFC proposes to convert the throw statement into an > expression to make it usable in arrow functions, the coalesce operator, as > well as the ternary/elvis operator. > > If you have any feedback, concerns, or if you want to express your > interest or lack thereof, let me know! > Looks like a reasonable change to me. Maybe interesting to compare with the ECMAScript and C# proposals you reference: The ECMAScript proposal (https://tc39.es/proposal-throw-expressions/) defines the throw expression as a very high precedence operator, rather than a low precedence one. There's discussion on that in https://github.com/tc39/proposal-throw-expressions/issues/10. Reading that thread, it seems like nobody actually wants the high precedence version, but there are some ECMAScript-specific issues with low precedence, because of conflicts with comma expressions. Thankfully that doesn't apply to us. The C# proposal ( https://docs.microsoft.com/en-us/dotnet/csharp/language-reference/proposals/csharp-7.0/throw-expression) limits the use of throw expressions to specific context only (in short lambdas and on the right hand side of ?: and ??). I'm personally not a fan of that, unless there's a technical motivation for that. If it's just about enforcing coding style, there's already plenty of weird expressions you can write right now. I don't want to add special cases to the language specification to enforce someone's style preferences. > The "Deprecate left-associative ternary operator"* RFC made it so that > parentheses are required when ternary operators are nested in > complicated statements. I should probably explicitly say here that the parentheses are required not because I think it is a good idea to require them, but to avoid changing the interpretation of an expression from one version to the next. Given that we did end up changing the precedence of the "." operator (rather than requiring parentheses), this choice is somewhat dubious now, and it would have been better to simply change the interpretation of the ternary in PHP 8 as well. Regards, Nikita
